Joo Ha Hwang, MD, PhD

All Publications

• Improving the Early Diagnosis of Gastric Cancer. Gastrointestinal endoscopy clinics of North America Huang, R. J., Hwang, J. H. 2021; 31 (3): 503-517

  Abstract

  Gastric cancer (GC) remains a leading cause of cancer morbidity and mortality worldwide. Outcomes from GC remain poor, especially in Western nations where cancer diagnosis is usually at advanced stages where curative resection is not possible. By contrast, nations of East Asia have adopted methods of population-level screening with improvements in stage of diagnosis and survival. In this review, the authors discuss the epidemiology of GC in Western populations, highlight at-risk populations who may benefit from screening, overview screening modalities, and discuss promising approaches to early GC detection.

  View details for DOI 10.1016/j.giec.2021.03.005

  View details for PubMedID 34053636

• An Approach to the Primary and Secondary Prevention of Gastric Cancer in the United States. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Huang, R. J., Epplein, M., Hamashima, C., Choi, I. J., Lee, E., Deapen, D., Woo, Y., Tran, T., Shah, S. C., Inadomi, J. M., Greenwald, D. A., Hwang, J. H. 2021

  Abstract

  /Aims: Gastric cancer (GC) remains a leading cause of mortality among certain racial, ethnic, and immigrant groups in the United States (US). The majority of GCs are diagnosed at advanced stages, and overall survival remains poor. There exist no structured national strategies for GC prevention in the US.On March 5-6, 2020 a Summit of researchers, policy makers, public funders, and advocacy leaders was convened at Stanford University to address this critical healthcare disparity. Following this Summit, a writing group was formed to critically evaluate the effectiveness, potential benefits, and potential harms of methods of primary and secondary prevention through structured literature review. This White Paper represents a consensus statement prepared by the writing group.The burden of GC is highly inequitably distributed in the US, and disproportionately falls on Asian, African American, Hispanic, and American Indian/Alaskan Native populations. In randomized controlled trials, strategies of Helicobacter pylori testing and treatment have been demonstrated to reduce GC-specific mortality. In well-conducted observational and ecological studies, strategies of endoscopic screening have been associated with reduced GC-specific mortality. Notably however, all randomized controlled trial data (for primary prevention), and the majority of observational data (for secondary prevention) are derived from non-US sources.There exists substantial, high-quality data supporting GC prevention derived from international studies. There is an urgent need for cancer prevention trials focused on high-risk immigrant and minority populations in the US. The authors offer recommendations on how strategies of primary and secondary prevention can be applied to the heterogeneous US population.

  View details for DOI 10.1016/j.cgh.2021.09.039

  View details for PubMedID 34624563

• A Summary of the 2020 Gastric Cancer Summit at Stanford University. Gastroenterology Huang, R. J., Koh, H., Hwang, J. H., Summit Leaders, Abnet, C. C., Alarid-Escudero, F., Amieva, M. R., Bruce, M. G., Camargo, M. C., Chan, A. T., Choi, I. J., Corvalan, A., Davis, J. L., Deapen, D., Epplein, M., Greenwald, D. A., Hamashima, C., Hur, C., Inadomi, J. M., Ji, H. P., Jung, H., Lee, E., Lin, B., Palaniappan, L. P., Parsonnet, J., Peek, R. M., Piazuelo, M. B., Rabkin, C. S., Shah, S. C., Smith, A., So, S., Stoffel, E. M., Umar, A., Wilson, K. T., Woo, Y., Yeoh, K. G. 2020

  View details for DOI 10.1053/j.gastro.2020.05.100

  View details for PubMedID 32707045

• Gastric per-oral endoscopic myotomy for severe post-lung transplant gastroparesis: A single-center experience. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation Podboy, A. J., Clarke, J. O., Nguyen, L. A., Mooney, J. J., Dhillon, G. S., Hwang, J. H. 2020

  View details for DOI 10.1016/j.healun.2020.06.019

  View details for PubMedID 32711933

• AGA White Paper: Interventional Endoscopic Ultrasound - Current Status and Future Directions. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association DeWitt, J. M., Arain, M. n., Chang, K. J., Sharaiha, R. n., Komanduri, S. n., Muthusamy, V. R., Hwang, J. H. 2020

  Abstract

  The evolution of endoscopic ultrasound (EUS) from a diagnostic to a therapeutic procedure has resulted in a paradigm shift towards endoscopic management of disease states that have previously required percutaneous or surgical approaches. The last few years have seen additional techniques and devices that have enabled endoscopists to expand its diagnostic and therapeutic capabilities. Some of these techniques were initially reported over a decade ago; however, with further device development and refinement in techniques there is potential for expanding the application of these techniques and new technologies to a broader group of interventional gastroenterologists. Lack of formalized training, devices and prospective data regarding their use in addition to a scarcity of guidelines on implementation of these technologies into clinical practice are contributing factors impeding the growth of the field of interventional EUS. In April 2019, the American Gastroenterological Association's Center for GI Innovation and Technology (CGIT) conducted its annual Tech Summit and a key session focused on interventional EUS. This article represents a white paper generated from the conference and discusses the published literature pertaining to the topic of interventional EUS and outlines a proposed framework for the implementation of interventional EUS techniques into clinical practice. Three primary areas of interventional EUS are addressed: (1) EUS-guided access; (2) EUS-guided tumor ablation; and (3) Endo-Hepatology. There was general agreement among participants on several key components. The introduction of these novel interventions requires better tools, more data on safety/outcomes and improved training for endoscopists. Participants also agreed that widespread implementation and use of these techniques will require support from GI societies and other key stakeholders including payers. Continued work by the GI societies and manufacturers to provide training programs, appropriate equipment/work environments and policies that motivate endoscopists to adopt new techniques is essential for growing the field of interventional EUS.

  View details for DOI 10.1016/j.cgh.2020.09.029

  View details for PubMedID 32950747

• Association of gastric intestinal metaplasia and East Asian ethnicity with the risk of gastric adenocarcinoma in a U.S. population. Gastrointestinal endoscopy Choi, A. Y., Strate, L. L., Fix, M. C., Schmidt, R. A., Ende, A. R., Yeh, M. M., Inadomi, J. M., Hwang, J. H. 2017

  Abstract

  Although the incidence of gastric cancer is higher than that of esophageal cancer in the United States, no screening or surveillance guidelines exist. The aim of this study is to evaluate the association between gastric intestinal metaplasia and the risk of gastric cancer in a U.S. tertiary care system with a large immigrant population.This is a retrospective case-control study with cases of biopsy-proven gastric cancer matched (by age and gender) to controls without gastric cancer who had undergone EGD. The presence of gastric intestinal metaplasia was ascertained from pathology reports. Other potential risk factors for gastric cancer were abstracted from medical records as follows: country of origin, Helicobacter pylori infection, family history of gastric cancer, alcohol consumption, smoking, and history of partial gastrectomy (Billroth I or II). Conditional logistic regression was used to identify independent risk factors for gastric cancer.One hundred fifty-two cases of gastric cancer were compared with 456 age- and gender-matched controls. The mean age was 66 years, and 57% were male. Multivariable analysis identified 2 significant predictors of gastric cancer: the presence of gastric intestinal metaplasia (odds ratio [OR], 9.3; 95% confidence interval [CI], 4.5-18.9; P < .001) and East Asian ethnicity (OR, 15.9; 95% CI, 5.8-43.6; P < .001).The presence of gastric intestinal metaplasia on endoscopy and East Asian ethnicity were significant risk factors for gastric cancer. Screening East Asian immigrants and surveying patients with gastric intestinal metaplasia may improve the rates of early detection of gastric cancer in the United States.

  View details for DOI 10.1016/j.gie.2017.11.010

  View details for PubMedID 29155082

• Screening and surveillance for gastric cancer in the United States: Is it needed? GASTROINTESTINAL ENDOSCOPY Kim, G. H., Liang, P. S., Bang, S. J., Hwang, J. H. 2016; 84 (1): 18-28

  Abstract

  Although the incidence of gastric cancer in the United States is relatively low, the incidence of gastric cancer is higher than for esophageal cancer, for which clear guidelines for screening and surveillance exist. With the increasing availability of endoscopic therapy, such as endoscopic submucosal dissection, for treating advanced dysplasia and early gastric cancer, establishing guidelines for screening and surveillance of patients who are at high risk of developing gastric cancer has the potential to diagnose and treat gastric cancer at an earlier stage and improve mortality from gastric cancer. The aims of this article were to review the data regarding the risk factors for developing gastric cancer, methods for gastric cancer screening, and results of national screening programs.A review of the existing literature related to the aims was performed.Risk factors for gastric cancer that were identified include race/ethnicity (East Asian, Russian, or South American), first-degree relative diagnosed with gastric cancer, positive Helicobacter pylori status, and presence of atrophic gastritis or intestinal metaplasia. Endoscopy has the highest rate of detecting gastric cancer compared with other gastric cancer screening methods. The national screening program in Japan has demonstrated a mortality reduction from gastric cancer based on cohort data.Gastric cancer screening with endoscopy should be considered in individuals who are immigrants from regions associated with a high risk of gastric cancer (East Asia, Russia, or South America) or who have a family history of gastric cancer. Those with findings of atrophic gastritis or intestinal metaplasia on screening endoscopy should undergo surveillance endoscopy every 1 to 2 years. Large prospective multicenter studies are needed to further identify additional risk factors for developing gastric cancer and to assess whether gastric cancer screening programs for high-risk populations in the United States would result in improved mortality.

  View details for DOI 10.1016/j.gie.2016.02.028

  View details for Web of Science ID 000378095000003

  View details for PubMedID 26940296

• High-intensity focused ultrasound: Current potential and oncologic applications AMERICAN JOURNAL OF ROENTGENOLOGY Dubinsky, T. J., Cuevas, C., Dighe, M. K., Kolokythas, O., Hwang, J. H. 2008; 190 (1): 191-199

  Abstract

  The objective of this article is to introduce the reader to the principles and applications of high-intensity focused ultrasound (HIFU).Although a great deal about HIFU physics is understood, its clinical applications are currently limited, and multiple trials are underway worldwide to determine its efficacy.

  View details for Web of Science ID 000252030700050

  View details for PubMedID 18094311

• [IDEN Consensus on Management of Antithrombotic Agents in Patients Undergoing Gastrointestinal Endoscopy]. The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi Kang, S. J., Tae, C. H., Bang, C. S., Shin, C. M., Jeong, Y. H., Choi, M., Hwang, J. H., Saito, Y., Chiu, P. W., Rerknimitr, R., Khor, C., Khien, V. V., Choi, K. D., Shim, K. N., Song, G. A., Lee, O. Y. 2024; 83 (6): 217-232

  Abstract

  Antithrombotic agents, including antiplatelet agent and anticoagulants are widely used in Korea due to increasing incidence of cardio-cerebrovascular disease and aging population. The management of patients using antithrombotic agents during endoscopic procedures is an important clinical challenge. Clinical practice guideline regarding this issue which was developed by the Korean Society of Gastrointestinal Endoscopy was published in 2020. However, since then, new evidence has emerged for the use of dual antiplatelet therapy and direct anticoagulant management, and revised guidelines were issued in the US and Europe. Accordingly, the previous guidelines were revised, cardiologists also participated in the development group, and the recommendations went through a consensus process among international experts. This guideline presents 14 recommendations made according to the Grading of Recommendations, Assessment, Development, and Evaluation methodology, and was reviewed by multidisciplinary experts. This guideline provides useful information that can assist endoscopists in the management of patients on antithrombotic agents who require diagnostic and elective therapeutic endoscopy. It will be revised as necessary to cover changes in technology, evidence, or other aspects of clinical practice.

  View details for DOI 10.4166/kjg.2024.040

  View details for PubMedID 38918035

• Magnesium and Esophageal Pain After Peroral Endoscopic Myotomy of the Esophagus: A Randomized, Double-Blind, Placebo-Controlled Trial. Anesthesia and analgesia Kim, R. K., Kim, J. W., Angelotti, T., Esquivel, M., Tsui, B. C., Hwang, J. H. 2024

  Abstract

  Postoperative esophageal pain occurs in 67% of patients after peroral endoscopic esophageal myotomy (POEM). Magnesium can act as a smooth muscle relaxant. This study investigated whether intraoperative magnesium can reduce postoperative esophageal pain in patients undergoing POEM.In this double-blind, placebo-controlled trial, 92 patients were randomized to receive either magnesium sulfate as a 50 mg.kg-1 (total body weight) bolus followed by an infusion at 25 mg.kg-1.hr-1, or 0.9% saline. Intraoperative analgesia was standardized in all patients. The primary outcome was the score from a validated, modified Esophageal Symptoms Questionnaire (ESQ) in the postanesthesia care unit (PACU). Pain scores, opioid requirements, and questionnaire scores were collected through postoperative day 1.ESQ scores were significantly lower in the magnesium group in the PACU (median [25th-75th], 24 [18-31] vs 35 [28-42]; median difference [95% confidence interval, CI], 10 [6-13]; P < .0001) and on postoperative day 1 (16 [14-23] vs 30 [24-35]; P < .0001). Less opioids were needed in the magnesium group in the PACU (mean ± standard deviation [SD] [99% CI], 4.7 ± 10 [1-9] mg vs 29 ± 21 [21-37] mg; P < .0001) and on postoperative day 1 (1 ± 3.7 [0-2.5] mg vs 13 ± 23 [4-23] mg; P = .0009). Pain scores were lower in the magnesium group in the PACU (0 [0-3] vs 5 [5-7]; P < .0001) and on postoperative day 1 (0 [0-2] vs 4 [3-5]; P < .0001).Patients undergoing POEM randomized to receive intraoperative magnesium had sustained reductions in esophageal discomfort severity and opioid requirements 24 hours after surgery.

  View details for DOI 10.1213/ANE.0000000000006990

  View details for PubMedID 38848261

• GASTRIC PER-ORAL ENDOSCOPIC MYOTOMY OUTCOMES STRATIFIED BY GASTROPARESIS ETIOLOGY AND RESPONSE TO PRIOR INTRAPYLORIC BOTULINUM TOXIN INJECTION - A RETROSPECTIVE ANALYSIS IDENTIFYING POSSIBLE PATIENT SELECTION CRITERIA Li, A., Callahan, M., Podboy, A., Hwang, J. MOSBY-ELSEVIER. 2024: AB1144

  View details for Web of Science ID 001278323004297

• A NOVEL RETRACTABLE ROBOTIC DEVICE FOR COLORECTAL ENDOSCOPIC SUBMUCOSAL DISSECTION Kim, S., Keum, B., Jeon, H., Choi, H., Kim, E., Jeen, Y., Chun, H., Hwang, J. MOSBY-ELSEVIER. 2024: AB775

  View details for Web of Science ID 001278323003085

• LONG TERM OUTCOMES OF NON-CURATIVE ENDOSCOPIC SUBMUCOSAL DISSECTION FOR COLORECTAL LESIONS Almario, J., Hiroyuki, A., Kumar, A., Schlachterman, A., Maluf-Filho, F., Othman, M., Jawaid, S., Teshima, C., Mosko, J., Draganov, P., Bechara, R., Schiavone, G., Le, J., Madaka, P., Kawaguti, F., Moura, R., Khalaf, M., King, W., Northern, N., Al-Shamali, H., Dang, F., Samarasena, J., Joseph, A., Friedland, S., Hwang, J., Li, A., Tomizawa, Y., Lucaciu, L., Subramanian, R., Despott, E., Ngamruengphong, S. MOSBY-ELSEVIER. 2024: AB469-AB470

  View details for Web of Science ID 001278323001422

• OUTCOMES OF ENDOSCOPIC SUBMUCOSAL DISSECTION FOR SUPERFICIAL ESOPHAGEAL SQUAMOUS NEOPLASMS: A MULTICENTER NORTH AMERICAN EXPERIENCE Subrahmanyan, R., Almario, J., Aihara, H., Kumar, A., Schlachterman, A., Friedland, S., Hwang, J., Othman, M., Jawaid, S., Ferri, L., Teshima, C., Mosko, J., Bechara, R., Samarasena, J., Yang, D., Ujiki, M., Tomizawa, Y., Schiavone, G., Madaka, P., Joseph, A., Li, A., Khalaf, M., Qatomah, A., Al-Shamali, H., Dang, F., Tavangar, A., Rwigema, J., King, W., Northern, N., Draganov, P., Ngamruengphong, S. MOSBY-ELSEVIER. 2024: AB992-AB993

  View details for Web of Science ID 001278323004037

• NORTH AMERICAN EXPERIENCE OF ENDOSCOPIC SUBMUCOSAL DISSECTION OF DISTAL RECTAL LESIONS EXTENDING TO THE DENTATE LINE - A LARGE SCALE MULTICENTER STUDY Malik, T., Khan, A., Gopakumar, H., Dahiya, D., Vohra, I., Zelt, C., Flanagan, M., Ladd, A., Aadam, A., Kang, A., Saeed, A., Khalaf, M., Othman, M., Ngamruengphong, S., Arayakarnkul, S., Yang, D., Bilal, M., DeLeon, M., Schlachterman, A., Madaka, P., Kamal, F., Kumar, A., Thompson, B., Kedia, P., Diehl, D., Shah, S., Sedarat, A., Wang, A., Dhaliwal, A., Mizrahi, M., Kahaleh, M., Andrawes, S., Dewitt, J., Obaitan, I., Ali, A., Hwang, J., Li, A., Friedland, S., Draganov, P., Sharma, N. MOSBY-ELSEVIER. 2024: AB470-AB471

  View details for Web of Science ID 001278323001423

• SAFETY AND EFFICACY OF PERORAL ENDOSCOPIC MYOTOMY (POEM) AS AN EMERGENCY TREATMENT IN HOSPITALIZED SEVERELY SYMPTOMATIC PATIENTS WITH ACHALSIA Fayyaz, F., Jagannath, P., Almardini, M., Bejjani, M., Mondragon, O., Robles, M., Schlachterman, A., Le, J., Chang, K., Dang, F., Hwang, J., Li, A., Sadeghi, E., Eleftheriadis, N., Bechara, R., Parvizian, M., Yoo, I., Pioche, M., Moll, F., Kim, R., Canakis, A., Othman, M., Khalaf, M., Estremera-Arevalo, F., Albeniz, E., Inoue, H., Shiwaku, H., Chung, C., Seewald, S., Pawa, R., Pawa, S., Khashab, M. MOSBY-ELSEVIER. 2024: AB959-AB960

  View details for Web of Science ID 001278323003393

• CLINICAL AND SEROLOGIC FEATURES OF AUTOIMMUNE METAPLASTIC ATROPHIC GASTRITIS: RESULTS OF AN ELECTRONIC HEALTH RECORDS COHORT Jove, A., Lin, C., Hwang, J., Fernandez-Becker, N., Huang, R. MOSBY-ELSEVIER. 2024: AB1095-AB1096

  View details for Web of Science ID 001278323004222

• A VALIDATED NOVEL PREDICTIVE TOOL FOR CLINICAL RESPONSE POST GASTRIC PER-ORAL ENDOSCOPIC MYOTOMY (G-POEM) AT 6-12 MONTHS: A LARGE INTERNATIONAL MULTI-CENTER COHORT STUDY Ichkhanian, Y., Salame, M., Hwang, J., Li, A., Yang, J., Broucek, J., Esfandyari, T., Joseph, S., Ujiki, M., Williams, A., Moremen, J., Gouda, Z., Schlachterman, A., Hugova, K., Martinek, J., Geng, C., Podboy, A., Wang, A., Lajin, M., Gregor, L., Albunni, H., Wo, J., Stainko, S., Saito, A., Siwiec, R., Nowak, T., Dewitt, J., Al-Haddad, M. MOSBY-ELSEVIER. 2024: AB1132-AB1133

  View details for Web of Science ID 001278323004281

• A COMPREHENSIVE ANALYSIS ON THE DIAGNOSIS AND THE MANAGEMENT OF CLINICAL FAILURE POST GASTRIC PERORAL ENDOSCOPIC MYOTOMY: AN INTERNATIONAL COHORT STUDY Ichkhanian, Y., Salame, M., Wo, J., Nowak, T., Stainko, S., Saito, A., Siwiec, R., Hwang, J., Li, A., Yang, J., Broucek, J., Esfandyari, T., Joseph, S., Ujiki, M., Williams, A., Moremen, J., Gouda, Z., Schlachterman, A., Hugova, K., Martinek, J., Geng, C., Podboy, A., Wang, A., Lajin, M., Gregor, L., Albunni, H., Dewitt, J., Al-Haddad, M. MOSBY-ELSEVIER. 2024: AB1130-AB1131

  View details for Web of Science ID 001278323004279

• A Novel Retractable Robotic Device for Colorectal Endoscopic Submucosal Dissection. Gut and liver Kim, S. H., Kim, C., Keum, B., Im, J., Won, S., Kim, B. G., Kim, K., Kwon, T., Hong, D., Jeon, H. J., Choi, H. S., Kim, E. S., Jeen, Y. T., Chun, H. J., Hwang, J. H. 2024

  Abstract

  : Appropriate tissue tension and clear visibility of the dissection area using traction are essential for effective and safe endoscopic submucosal dissection (ESD). In this study, we developed a retractable robot-assisted traction device and evaluated its performance in colorectal ESD.: An experienced endoscopist performed ESD 18 times on an ex vivo porcine colon using the robot and 18 times using the conventional method. The outcome measures were procedure time, dissection speed, procedure-related adverse events, and blind dissection rate.: Thirty-six colonic lesions were resected from ex vivo porcine colon samples. The total procedure time was significantly shorter in robot-assisted ESD (RESD) than in conventional ESD (CESD) (20.1±4.1 minutes vs 34.3±8.3 minutes, p<0.05). The submucosal dissection speed was significantly faster in the RESD group than in the CESD group (36.8±9.2 mm2/min vs 18.1±4.7 mm2/min, p<0.05). The blind dissection rate was also significantly lower in the RESD group (12.8%±3.4% vs 35.1%±3.9%, p<0.05). In an in vivo porcine feasibility study, the robotic device was attached to a colonoscope and successfully inserted into the proximal colon without damaging the colonic wall, and ESD was successfully performed.: The dissection speed and safety profile improved significantly with the retractable RESD. Thus, our robotic device has the potential to provide simple, effective, and safe multidirectional traction during colonic ESD.

  View details for DOI 10.5009/gnl230280

  View details for PubMedID 38712393

• Robot-assisted gastric endoscopic submucosal dissection significantly improves procedure time at challenging dissection locations. Surgical endoscopy Kim, S. H., Kwon, T., Choi, H. S., Kim, C., Won, S., Jeon, H. J., Kim, E. S., Keum, B., Jeen, Y. T., Hwang, J. H., Chun, H. J. 2024

  Abstract

  Endoscopic submucosal dissection (ESD) is the standard treatment for early malignant stomach lesions. However, this procedure is technically demanding and carries a high complication risk. The level of difficulty in performing ESD is influenced by the location of the lesion. In our study, we aimed to investigate and analyze the effectiveness of robot-assisted ESD for lesions situated in challenging locations within the stomach.We developed a gastric simulator that could be used to implement various gastric ESD locations. An EndoGel (Sunarrow, Tokyo, Japan) was attached to the simulator for the dissection procedures. Robot-assisted or conventional ESD was performed at challenging or easy locations by two ESD-trainee endoscopists.The procedure time was remarkably shorter for robotic ESD than conventional dissection at challenging locations (6.2 vs. 10.2 min, P < 0.05), mainly due to faster dissection (220.3 vs. 101.9 mm2/min, P < 0.05). The blind dissection rate was significantly lower with robotic ESD than with the conventional method (17.6 vs. 35.2%, P < 0.05) at challenging locations.The procedure time was significantly shortened when robot-assisted gastric ESD procedures were performed at challenging locations. Therefore, our robotic device provides simple, effective, and safe multidirectional traction for endoscopic submucosal dissection at challenging locations, thereby reducing difficulty of the procedure.

  View details for DOI 10.1007/s00464-024-10743-9

  View details for PubMedID 38467861

  View details for PubMedCentralID 5018178

• International Digestive Endoscopy Network consensus on the management of antithrombotic agents in patients undergoing gastrointestinal endoscopy. Clinical endoscopy Kang, S. J., Tae, C. H., Bang, C. S., Shin, C. M., Jeong, Y. H., Choi, M., Hwang, J. H., Saito, Y., Chiu, P. W., Rerknimitr, R., Khor, C., Khien, V. V., Choi, K. D., Shim, K. N., Song, G. A., Lee, O. Y. 2024; 57 (2): 141-157

  Abstract

  Antithrombotic agents, including antiplatelet agents and anticoagulants, are widely used in Korea because of the increasing incidence of cardiocerebrovascular disease and the aging population. The management of patients using antithrombotic agents during endoscopic procedures is an important clinical challenge. The clinical practice guidelines for this issue, developed by the Korean Society of Gastrointestinal Endoscopy, were published in 2020. However, new evidence on the use of dual antiplatelet therapy and direct anticoagulant management has emerged, and revised guidelines have been issued in the United States and Europe. Accordingly, the previous guidelines were revised. Cardiologists were part of the group that developed the guideline, and the recommendations went through a consensus-reaching process among international experts. This guideline presents 14 recommendations made based on the Grading of Recommendations, Assessment, Development, and Evaluation methodology and was reviewed by multidisciplinary experts. These guidelines provide useful information that can assist endoscopists in the management of patients receiving antithrombotic agents who require diagnostic and elective therapeutic endoscopy. It will be revised as necessary to cover changes in technology, evidence, or other aspects of clinical practice.

  View details for DOI 10.5946/ce.2024.002

  View details for PubMedID 38556472

• Safety, Efficacy and Clinical Utility of the 5.1mm EndoRotor Powered Debridement Catheter for Treatment of Walled-Off Pancreatic Necrosis. Gastrointestinal endoscopy Shinn, B., Burdick, J., Berk, K., Hwang, J. H., El-Dika, S., Juakiem, W., Han, S., Krishna, S., Khashab, M. A., Mony, S., Kadkhodayan, K., Khara, H. S., Ahmed, A. M., Boortalary, T., Agnohortri, A., Kumar, A., Chiang, A., Kamal, F., Schlachterman, A., Loren, D., Kowalski, T. 2024

  Abstract

  Direct endoscopic necrosectomy (DEN) is a recommended strategy for treatment of walled-off-necrosis (WON). DEN uses a variety of devices including the EndoRotor (Interscope, Inc.) debridement catheter. Recently, a 5.1 mm EndoRotor with increased chamber size and rate of tissue removal was introduced. The aim of this study was to assess the efficacy and safety of this device.A multi-center cohort study was conducted at eight institutions including patients who underwent DEN with the 5.1 mm EndoRotor. The primary outcome was the number of DEN sessions needed for WON resolution. Secondary outcomes included the average percent reduction in solid WON debris and decrease in WON area per session, total time spent performing EndoRotor therapy for WON resolution, and adverse events.64 procedures in 41 patients were included. For patients in which the 5.1 mm EndoRotor catheter was the sole therapeutic modality, an average of 1.6 DEN sessions resulted in WON resolution with an average cumulative time of 85.5 minutes. Of the 21 procedures with data regarding percent of solid debris, the average reduction was 85% +/- 23% per session. Of the 19 procedures with data regarding WON area, the mean area significantly decreased from 97.6 +/- 72.0 cm2 to 27.1 +/- 35.5 cm2 (p<0.001) per session. Adverse events included two intra-procedural LAMS dislodgements managed endoscopically and three perforations none of which were related to EndoRotor. Bleeding was reported in seven cases, none required embolic or surgical therapy and two required blood transfusions.This is the first multi-center retrospective study to investigate the efficacy and safety of the 5.1 mm EndoRotor catheter for WON. Results from this study showed an average of 1.6 DEN sessions were needed to achieve WON resolution with an 85% single session reduction in solid debris and a 70% single session decrease in WON area with minimal adverse events.

  View details for DOI 10.1016/j.gie.2024.02.016

  View details for PubMedID 38431104

• Risk of Gastric Adenocarcinoma in a Multiethnic Population undergoing Routine Care: an Electronic Health Records Cohort Study. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology Huang, R. J., Huang, E. S., Mudiganti, S., Chen, T., Martinez, M. C., Ramrakhiani, S., Han, S. S., Hwang, J. H., Palaniappan, L. P., Liang, S. Y. 2024

  Abstract

  Gastric adenocarcinoma (GAC) is often diagnosed at advanced stages and portends a poor prognosis. We hypothesized that electronic health records (EHR) could be leveraged to identify individuals at highest risk for GAC from the population seeking routine care.This was a retrospective cohort study, with endpoint of GAC incidence as ascertained through linkage to an institutional tumor registry. We utilized 2010-2020 data from the Palo Alto Medical Foundation, a large multispecialty practice serving Northern California. The analytic cohort comprised individuals aged 40-75 receiving regular ambulatory care. Variables collected included demographic, medical, pharmaceutical, social, and familial data. Electronic phenotyping was based on rules-based methods.The cohort comprised 316,044 individuals and ~2 million person-years (p-y) of observation. 157 incident GACs occurred (incidence 7.9 per 100,000 p-y), of which 102 were non-cardia GACs (incidence 5.1 per 100,000 p-y). In multivariable analysis, male sex (HR 2.2, 95% CI 1.6-3.1), older age, Asian race (HR 2.5, 95% CI 1.7-3.7), Hispanic ethnicity (HR 1.9, 95% CI 1.1-3.3), atrophic gastritis (HR 4.6, 95% CI 2.2-9.3), and anemia (HR 1.9, 95% CI 1.3-2.6) were associated with GAC risk; use of non-steroidal anti-inflammatory drug was inversely associated (HR 0.3, 95% CI 0.2-0.5). Older age, Asian race, Hispanic ethnicity, atrophic gastritis, and anemia were associated with non-cardia GAC.Routine EHR data can stratify the general population for GAC risk.Such methods may help triage populations for targeted screening efforts, such as upper endoscopy.

  View details for DOI 10.1158/1055-9965.EPI-23-1200

  View details for PubMedID 38231023

• Peroral Endoscopic Myotomy For Spastic Esophageal Dysmotility Among Opioid Users: Multicenter Propensity Score Match Study. Gastrointestinal endoscopy Bani Fawwaz, B., Zhang, Y., Farooq, A., Gorrepati, V. S., Forde, J. F., Canakis, A., Kim, R., Ma, M., Benias, P., Che, S., Ujiki, M. B., Li, A. A., Hwang, J. H., Eke, C., Kedia, P., Yu, A., Inayat, I., Khalaf, M., Othman, M., Jawaid, S., Hasan, M. K., Sharma, N., Pomenti, S., Sethi, A., Draganov, P. V., Yang, D. 2024

  Abstract

  Opioid induced esophageal disorder (OIED) often presents as spastic esophageal disorders (SEDs) and esophagogastric junction outflow obstruction (EGJOO). We aimed to evaluate and compare clinical outcomes of POEM for SEDs and EGJOO among opioid users and non-users.Propensity-score (PS) match study of consecutive opioid users and non-users who underwent POEM for SEDs and EGJOO between January 2018 to September 2022. The following covariates were used for PS calculation: age, sex, duration of symptoms, Eckardt score, type of motility disorder, and length of myotomy during POEM. Clinical response was defined as post-POEM Eckardt score ≤3.A total of 277 consecutive patients underwent POEM during the study period. PS match resulted in the selection of 64 pairs of strictly 1:1 matched patients (n=128) with no statistically significant differences in demographics, baseline and procedural characteristics or in the parameters considered for the PS between the two groups. Clinical response to POEM was significantly lower among opioid users (51/64; 79.7%) vs non-users (60/64; 93.8%) (p=0.03) at a median follow-up of 18 months. Among opioid users, higher opioid dose (>60 morphine milligram equivalents per day) was associated with a higher likelihood for failure to respond to POEM (Odds Ratio: 4.59; 95% CI: 1.31-3.98; p=0.02).Clinical response to POEM for SEDs and EGJOO is significantly lower among opioid users vs. non-users. There was dose-relationship between opioids and response to POEM, with higher daily opioid usage associated with a higher likelihood of treatment failure.

  View details for DOI 10.1016/j.gie.2023.12.034

  View details for PubMedID 38184116

• Endoscopic Resection of Early Luminal Cancer. Gastrointestinal endoscopy clinics of North America Choi, H. S., Hwang, J. H. 2024; 34 (1): 51-78

  Abstract

  Gastrointestinal cancers can have severe consequences if diagnosed at a late stage but can be cured when detected and resected at an early stage. In recent years, the significance of endoscopic screening for gastrointestinal cancers has been established, leading to the identification of early-stage cancers and precancerous lesions. Consequently, endoscopic removal of gastrointestinal tumors has emerged as an effective means of cancer treatment and prevention. This article delves into the indications, techniques, and safety measures associated with endoscopic resection of early-stage luminal cancer within the gastrointestinal tract.

  View details for DOI 10.1016/j.giec.2023.07.002

  View details for PubMedID 37973231

• The <i>Helicobacter pylori</i> Genome Project: insights into <i>H. pylori</i> population structure from analysis of a worldwide collection of complete genomes NATURE COMMUNICATIONS Thorell, K., Munoz-Ramirez, Z. Y., Wang, D., Sandoval-Motta, S., Agostini, R., Ghirotto, S., Torres, R. C., Falush, D., Camargo, M., Rabkin, C. S., HpGP Research Network 2023; 14 (1): 8184

  Abstract

  Helicobacter pylori, a dominant member of the gastric microbiota, shares co-evolutionary history with humans. This has led to the development of genetically distinct H. pylori subpopulations associated with the geographic origin of the host and with differential gastric disease risk. Here, we provide insights into H. pylori population structure as a part of the Helicobacter pylori Genome Project (HpGP), a multi-disciplinary initiative aimed at elucidating H. pylori pathogenesis and identifying new therapeutic targets. We collected 1011 well-characterized clinical strains from 50 countries and generated high-quality genome sequences. We analysed core genome diversity and population structure of the HpGP dataset and 255 worldwide reference genomes to outline the ancestral contribution to Eurasian, African, and American populations. We found evidence of substantial contribution of population hpNorthAsia and subpopulation hspUral in Northern European H. pylori. The genomes of H. pylori isolated from northern and southern Indigenous Americans differed in that bacteria isolated in northern Indigenous communities were more similar to North Asian H. pylori while the southern had higher relatedness to hpEastAsia. Notably, we also found a highly clonal yet geographically dispersed North American subpopulation, which is negative for the cag pathogenicity island, and present in 7% of sequenced US genomes. We expect the HpGP dataset and the corresponding strains to become a major asset for H. pylori genomics.

  View details for DOI 10.1038/s41467-023-43562-y

  View details for Web of Science ID 001142897900001

  View details for PubMedID 38081806

  View details for PubMedCentralID PMC10713588

• Updated endoscopic treatment of postoperative pancreatic fluid collections INTERNATIONAL JOURNAL OF GASTROINTESTINAL INTERVENTION Hwang, J. 2023; 12: S86

  View details for DOI 10.18528/ijgii23S1504

  View details for Web of Science ID 001178273500055

• Detection and surveillance of gastric cancer precursors: evolving guidelines and technologies ANNALS OF LAPAROSCOPIC AND ENDOSCOPIC SURGERY Koh, J., Shunt, M., Hwang, J., Huang, R. J. 2023; 8

  View details for DOI 10.21037/ales-23-13

  View details for Web of Science ID 001088917900002

• A spatially mapped gene expression signature for intestinal stem-like cells identifies high-risk precursors of gastric cancer. bioRxiv : the preprint server for biology Huang, R. J., Wichmann, I. A., Su, A., Sathe, A., Shum, M. V., Grimes, S. M., Meka, R., Almeda, A., Bai, X., Shen, J., Nguyen, Q., Amieva, M. R., Hwang, J. H., Ji, H. P. 2023

  Abstract

  Gastric intestinal metaplasia (GIM) is a precancerous lesion that increases gastric cancer (GC) risk. The Operative Link on GIM (OLGIM) is a combined clinical-histopathologic system to risk-stratify patients with GIM. The identification of molecular biomarkers that are indicators for advanced OLGIM lesions may improve cancer prevention efforts.This study was based on clinical and genomic data from four cohorts: 1) GAPS, a GIM cohort with detailed OLGIM severity scoring (N=303 samples); 2) the Cancer Genome Atlas (N=198); 3) a collation of in-house and publicly available scRNA-seq data (N=40), and 4) a spatial validation cohort (N=5) consisting of annotated histology slides of patients with either GC or advanced GIM. We used a multi-omics pipeline to identify, validate and sequentially parse a highly-refined signature of 26 genes which characterize high-risk GIM.Using standard RNA-seq, we analyzed two separate, non-overlapping discovery (N=88) and validation (N=215) sets of GIM. In the discovery phase, we identified 105 upregulated genes specific for high-risk GIM (defined as OLGIM III-IV), of which 100 genes were independently confirmed in the validation set. Spatial transcriptomic profiling revealed 36 of these 100 genes to be expressed in metaplastic foci in GIM. Comparison with bulk GC sequencing data revealed 26 of these genes to be expressed in intestinal-type GC. Single-cell profiling resolved the 26-gene signature to both mature intestinal lineages (goblet cells, enterocytes) and immature intestinal lineages (stem-like cells). A subset of these genes was further validated using single-molecule multiplex fluorescence in situ hybridization. We found certain genes (TFF3 and ANPEP) to mark differentiated intestinal lineages, whereas others (OLFM4 and CPS1) localized to immature cells in the isthmic/crypt region of metaplastic glands, consistent with the findings from scRNAseq analysis.using an integrated multi-omics approach, we identified a novel 26-gene expression signature for high-OLGIM precursors at increased risk for GC. We found this signature localizes to aberrant intestinal stem-like cells within the metaplastic microenvironment. These findings hold important translational significance for future prevention and early detection efforts.

  View details for DOI 10.1101/2023.09.20.558462

  View details for PubMedID 37786704

  View details for PubMedCentralID PMC10541579

• Low Delayed Bleeding and High Complete Closure Rate of Mucosal Defects with the Novel Through-The-Scope Dual Action Tissue Clip After Endoscopic Resection of Large Non-Pedunculated Colorectal Lesions. Gastrointestinal endoscopy Mohammed, A. S., Robalino Gonzaga, E., Hasan, M. K., Saeed, A., Friedland, S., Bilal, M., Sharma, N., Jawaid, S., Othman, M., Khalaf, M. A., Hwang, J. H., Viana, A., Singh, S., Hayat, M., Cosgrove, N. D., Jain, D., Arain, M. A., Kadkhodayan, K. S., Yang, D. 2023

  Abstract

  Complete closure following endoscopic resection (ER) of large non-pedunculated colorectal lesions (LNPCLs) can reduce delayed bleeding but is challenging with conventional through-the-scope (TTS) clips alone. The novel dual action tissue (DAT) has clip arms that open and close independent of each other, facilitating tissue approximation. We aimed to evaluate the rate of complete closure and delayed bleeding with the DAT clip after ER of LNPCLs.Multicenter prospective cohort study of all patients who underwent defect closure with the DAT clip following endoscopic mucosal resection (EMR) or submucosal dissection (ESD) of LNPCLs ≥ 20 mm from July 2022 to May 2023. Delayed bleeding was defined as bleeding event requiring hospitalization, blood transfusion or any intervention within 30 days after the procedure. Complete closure was defined as apposition of mucosal defect margins without visible submucosal areas < 3 mm along the closure line.A total of 107 patients (median age 64 years; 42.5% women) underwent EMR (n=63) or ESD (n=44) of LNPCLs (median size 40 mm; 74.8% right colon) followed by defect closure. Complete closure was achieved in 96.3% (n=103) with a mean of 1.4±0.6 DAT and 2.9±1.8 TTS clips. Delayed bleeding occurred in one patient (0.9%) without requiring additional interventions.The use of the DAT clip in conjunction with TTS clips achieved high complete defect closure after ER of large LNPCLs and was associated with a 0.9% delayed bleeding rate. Future comparative trials and formal cost-analyses are needed to validate these findings.

  View details for DOI 10.1016/j.gie.2023.07.025

  View details for PubMedID 37481003

• Multicenter evaluation of recurrence in endoscopic submucosal dissection and endoscopic mucosal resection in the colon: A Western perspective. World journal of gastrointestinal endoscopy Wei, M. T., Zhou, M. J., Li, A. A., Ofosu, A., Hwang, J. H., Friedland, S. 2023; 15 (6): 458-468

  Abstract

  BACKGROUND: While colon endoscopic mucosal resection (EMR) is an effective technique, removal of larger polyps often requires piecemeal resection, which can increase recurrence rates. Endoscopic submucosal dissection (ESD) in the colon offers the ability for en bloc resection and is well-described in Asia, but there are limited studies comparing ESD vs EMR in the West.AIM: To evaluate different techniques in endoscopic resection of large polyps in the colon and to identify factors for recurrence.METHODS: The study is a retrospective comparison of ESD, EMR and knife-assisted endoscopic resection performed at Stanford University Medical Center and Veterans Affairs Palo Alto Health Care System between 2016 and 2020. Knife-assisted endoscopic resection was defined as use of electrosurgical knife to facilitate snare resection, such as for circumferential incision. Patients ≥ 18 years of age undergoing colonoscopy with removal of polyp(s) ≥ 20 mm were included. The primary outcome was recurrence on follow-up.RESULTS: A total of 376 patients and 428 polyps were included. Mean polyp size was greatest in the ESD group (35.8 mm), followed by knife-assisted endoscopic resection (33.3 mm) and EMR (30.5 mm) (P < 0.001). ESD achieved highest en bloc resection (90.4%) followed by knife-assisted endoscopic resection (31.1%) and EMR (20.2%) (P < 0.001). A total of 287 polyps had follow-up (67.1%). On follow-up analysis, recurrence rate was lowest in knife-assisted endoscopic resection (0.0%) and ESD (1.3%) and highest in EMR (12.9%) (P = 0.0017). En bloc polyp resection had significantly lower rate of recurrence (1.9%) compared to non-en bloc (12.0%, P = 0.003). On multivariate analysis, ESD (in comparison to EMR) adjusted for polyp size was found to significantly reduce risk of recurrence [adjusted hazard ratio 0.06 (95%CI: 0.01-0.57, P = 0.014)].CONCLUSION: In our study, EMR had significantly higher recurrence compared to ESD and knife-assisted endoscopic resection. We found factors including resection by ESD, en bloc removal, and use of circumferential incision were associated with significantly decreased recurrence. While further studies are needed, we have demonstrated the efficacy of ESD in a Western population.

  View details for DOI 10.4253/wjge.v15.i6.458

  View details for PubMedID 37397977

• ENDOSCOPIC SUBMUCOSAL DISSECTION OF ESOPHAGEAL ADENOCARCINOMA DEEMED PATHOLOGICALLY CURATIVE RESULTS IN FEW RECURRENCES AT LONG-TERM SURVEILLANCE: A NORTH AMERICAN STUDY Schenck, R., Bhatt, A., Ngamruengphong, S., Friedland, S., Aihara, H., Dewitt, J., Patrie, J., Foster, S., Joseph, A., Arayakarnkul, S., Mercado, M., Northern, N., Aadam, A., Othman, M., Sethi, A., Sharaiha, R., Nishimura, M., Fukami, N., Hwang, J., Yang, D., Draganov, P., Wang, A. MOSBY-ELSEVIER. 2023: AB1105-AB1106

  View details for Web of Science ID 001038022802459

• CLINICAL OUTCOMES OF PERORAL ENDOSCOPIC MYOTOMY (POEM) IN PATIENTS WITH SPASTIC ESOPHAGEAL MOTILITY DISORDERS ON CHRONIC OPIOID USE: A MULTICENTER STUDY Fawwaz, B., Gorrepati, V., Forde, J., Canakis, A., Gerges, P., Farooq, A., Kim, R., Ma, M., Benias, P., Che, S., Ujiki, M., Li, A., Hwang, J., Eke, C., Kedia, P., Hayat, M., Inayat, I., Khalaf, M., Othman, M., Jawaid, S., Hasan, M., Draganov, P., Yang, D. MOSBY-ELSEVIER. 2023: AB1083-AB1084

  View details for Web of Science ID 001038022802429

• ASGE Upper GI Tract: A Potpourri of AI, Imaging, Resection and Myotomy AN ANALYSIS OF RISK FACTORS FOR GASTRIC INTESTINAL METAPLASIAdTHE STANFORD GAPS STUDY Shum, M., Huang, R., Kim, J., Hwang, J. MOSBY-ELSEVIER. 2023: AB1234-AB1235

  View details for Web of Science ID 001038022803057

• ENDOSCOPIC SUBMUCOSAL DISSECTION OF ESOPHAGEAL ADENOCARCINOMA DEEMED PATHOLOGICALLY CURATIVE RESULTS IN FEW RECURRENCES AT LONG-TERM SURVEILLANCE: A NORTH AMERICAN STUDY Schenck, R., Bhatt, A., Ngamruengphong, S., Friedland, S., Aihara, H., Dewitt, J., Patrie, J., Foster, S., Joseph, A., Arayakarnkul, S., Mercado, M., Northern, N., Aadam, A., Othman, M., Sethi, A., Sharaiha, R., Nishimura, M., Fukami, N., Hwang, J., Yang, D., Draganov, P., Wang, A. MOSBY-ELSEVIER. 2023: AB1018-AB1019

  View details for Web of Science ID 001038022802336

• Controlling Gastric Cancer in a World of Heterogeneous Risk. Gastroenterology Huang, R. J., Laszkowska, M., In, H., Hwang, J. H., Epplein, M. 2023

  Abstract

  Gastric cancer (GC) is a leading cause of global mortality, but also a cancer whose footprint is highly unequal. This review aims to define global disease epidemiology, critically appraise strategies of prevention and disease attenuation, and assess how these strategies could be applied to improve outcomes from GC in a world of variable risk and disease burden. Strategies of primary prevention focus on improving the detection and eradication of the main environmental risk factor, Helicobacter pylori. In certain countries of high incidence, endoscopic or radiographic screening of the asymptomatic general population has been adopted as a means of secondary prevention. By contrast, identification and targeted surveillance of individuals with precancerous lesions (such as intestinal metaplasia) is being increasingly embraced in nations of low incidence. This review will also highlight existing knowledge gaps in GC prevention, as well as the role of emerging technologies for early detection and risk stratification.

  View details for DOI 10.1053/j.gastro.2023.01.018

  View details for PubMedID 36706842

• Understanding the Principles of Electrosurgery for Endoscopic Surgery and Third Space Endoscopy. Gastrointestinal endoscopy clinics of North America Li, A. A., Zhou, M. J., Hwang, J. H. 2023; 33 (1): 29-40

  Abstract

  Electrosurgery is the application of high-frequency electrical alternating current to biologic tissue to cut, coagulate, desiccate, and/or fulgurate. Electrosurgery is commonly used in gastrointestinal endoscopy, with applications including biliary sphincterotomy, polypectomy, hemostasis, the ablation of lesions, and endoscopic surgery. Understanding electrosurgical principles is important in endoscopic surgery to achieve the desired therapeutic effect, optimize procedural outcomes, and minimize risks or adverse events. This article describes fundamental principles that apply to electrosurgical units, operator technique, and practical considerations for achieving desired tissue effects in endoscopic surgery; and provides practical guidance and safety considerations when using electrosurgical units in endoscopic surgery.

  View details for DOI 10.1016/j.giec.2022.07.001

  View details for PubMedID 36375884

• Risk of Proximal Gastrointestinal Cancer after Positive Fecal Immunochemical Test. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Zhou, M. J., Singh, G., Hwang, J. H., Ladabaum, U. 2022

  View details for DOI 10.1016/j.cgh.2022.11.032

  View details for PubMedID 36464140

• Management of Helicobacter pylori Infection: A Comparison between Korea and the United States. Gut and liver Kim, S. E., Hwang, J. H. 2022; 16 (4): 503-514

  Abstract

  Helicobacter pylori has been well known to cause gastritis, peptic ulcers, mucosa-associated lymphoid tissue, and gastric cancer. The importance of H. pylori eradication has been emphasized; however, the management of H. pylori infection is difficult in clinical practice. In both Eastern and Western countries, there has been a constant interest in confirming individuals who should be tested and treated for H. pylori infection and developing methods to diagnose H. pylori infection. Many studies have been implemented to successfully eradicate H. pylori, and various combinations of eradication regimens for H. pylori infection have been suggested worldwide. Based on the findings of previous studies, a few countries have published their own guidelines that are appropriate for their country; however, these country-specific guidelines may differ depending on the circumstances in each country. Evidence-based guidelines and clinical practice updates for the treatment of H. pylori infection have been published in Korea and the United States in 2021. This review will summarize the similarities and differences in the management of H. pylori infection in Korea and the United States, focusing on indications, diagnosis, and treatments based on recent guidelines and recommendations in both countries.

  View details for DOI 10.5009/gnl210224

  View details for PubMedID 35843686

  View details for PubMedCentralID PMC9289837

• The Gastric Cancer Registry: A Genomic Translational Resource for Multidisciplinary Research in Gastric Cancer. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology Almeda, A. F., Grimes, S. M., Lee, H., Greer, S., Shin, G., McNamara, M., Hooker, A. C., Arce, M. M., Kubit, M., Schauer, M. C., Van Hummelen, P., Ma, C., Mills, M. A., Huang, R. J., Hwang, J. H., Amieva, M. R., Han, S. S., Ford, J. M., Ji, H. P. 2022

  Abstract

  Gastric cancer (GC) is a leading cause of cancer morbidity and mortality. Developing information systems which integrate clinical and genomic data may accelerate discoveries to improve cancer prevention, detection, and treatment. To support translational research in GC, we developed the GC Registry (GCR), a North American repository of clinical and cancer genomics data.Participants self-enrolled online. Entry criteria into the GCR included the following: (1) diagnosis of GC, (2) history of GC in a first- or second-degree relative, or (3) known germline mutation in the gene CDH1. Participants provided demographic and clinical information through a detailed survey. Some participants provided specimens of saliva and tumor samples. Tumor samples underwent exome sequencing, whole genome sequencing and transcriptome sequencing.From 2011-2021, 567 individuals registered and returned the clinical questionnaire. For this cohort 65% had a personal history of GC, 36% reported a family history of GC and 14% had a germline CDH1 mutation. 89 GC patients provided tumor samples. For the initial study, 41 tumors were sequenced using next generation sequencing. The data was analyzed for cancer mutations, copy number variations, gene expression, microbiome, neoantigens, immune infiltrates, and other features. We developed a searchable, web-based interface (the GCR Genome Explorer) to enable researchers access to these datasets.The GCR is a unique, North American GC registry which integrates clinical and genomic annotation.Available for researchers through an open access, web-based explorer, the GCR Genome Explorer will accelerate collaborative GC research across the United States and world.

  View details for DOI 10.1158/1055-9965.EPI-22-0308

  View details for PubMedID 35771165

• A Comparison of Logistic Regression Against Machine Learning Algorithms for Gastric Cancer Risk Prediction Within Real-World Clinical Data Streams. JCO clinical cancer informatics Huang, R. J., Kwon, N. S., Tomizawa, Y., Choi, A. Y., Hernandez-Boussard, T., Hwang, J. H. 2022; 6: e2200039

  Abstract

  Noncardia gastric cancer (NCGC) is a leading cause of global cancer mortality, and is often diagnosed at advanced stages. Development of NCGC risk models within electronic health records (EHR) may allow for improved cancer prevention. There has been much recent interest in use of machine learning (ML) for cancer prediction, but few studies comparing ML with classical statistical models for NCGC risk prediction.We trained models using logistic regression (LR) and four commonly used ML algorithms to predict NCGC from age-/sex-matched controls in two EHR systems: Stanford University and the University of Washington (UW). The LR model contained well-established NCGC risk factors (intestinal metaplasia histology, prior Helicobacter pylori infection, race, ethnicity, nativity status, smoking history, anemia), whereas ML models agnostically selected variables from the EHR. Models were developed and internally validated in the Stanford data, and externally validated in the UW data. Hyperparameter tuning of models was achieved using cross-validation. Model performance was compared by accuracy, sensitivity, and specificity.In internal validation, LR performed with comparable accuracy (0.732; 95% CI, 0.698 to 0.764), sensitivity (0.697; 95% CI, 0.647 to 0.744), and specificity (0.767; 95% CI, 0.720 to 0.809) to penalized lasso, support vector machine, K-nearest neighbor, and random forest models. In external validation, LR continued to demonstrate high accuracy, sensitivity, and specificity. Although K-nearest neighbor demonstrated higher accuracy and specificity, this was offset by significantly lower sensitivity. No ML model consistently outperformed LR across evaluation criteria.Drawing data from two independent EHRs, we find LR on the basis of established risk factors demonstrated comparable performance to optimized ML algorithms. This study demonstrates that classical models built on robust, hand-chosen predictor variables may not be inferior to data-driven models for NCGC risk prediction.

  View details for DOI 10.1200/CCI.22.00039

  View details for PubMedID 35763703

• Role of gastric per-oral endoscopic myotomy (G-POEM) in post-lung transplant patients: a multicenter experience. Endoscopy international open Ichkhanian, Y., Hwang, J. H., Ofosu, A., Li, A. A., Szvarca, D., Draganov, P. V., Yang, D., Alsheik, E., Zuchelli, T., Piraka, C., Mony, S., Khashab, M. A. 2022; 10 (6): E832-E839

  Abstract

  Background and study aims Gastroparesis post-lung transplant (LTx) can lead to increased risk of gastroesophageal reflux (GER) and accelerated graft dysfunction. We aimed to evaluate the efficacy and safety of gastric per-oral endoscopic myotomy (G-POEM), a promising tool in patients with refractory gastroparesis, for managing refractory gastroparesis and GER in post-LTx patients. Patents and methods This was a multicenter retrospective study on post-LTx patients who underwent G-POEM for management of gastroparesis and GER that were refractory to standard medical therapy. The primary outcome was clinical success post-G-POEM. Secondary outcomes included the rate of post-G-POEM objective esophageal pH exam normalization, rate of gastric emptying scintigraphy (GES) normalization, technical success, and adverse events. Results A total of 20 patients (mean age 54.7 ± 14.1 years, Female 50 %) underwent G-POEM at a median time of 13 months (interquartile range 6.5-13.5) post-LTx. All G-POEM procedures were technically successful. Clinical success was achieved in 17 (85 %) patients during a median follow-up time of 8.9 (IQR: 3-17) months post-G-POEM. Overall GCSI and two of its subscales (bloating and postprandial fullness/early satiety) improved significantly following G-POEM. Two patients (10 %) developed post-procedural AEs (delayed bleeding 1, pyloric stenosis 1, both moderate in severity). Post-G-POEM GES improvement was achieved in 12 of 16 patients (75 %). All 20 patients were on proton pump inhibitors pre-G-POEM, as opposed to five post-G-POEM. Post-G-POEM PH study normalization was noted in nine of 10 patients (90 %) who underwent both pre- and post-G-poem pH testing. Conclusions G-POEM is a promising noninvasive therapeutic tool for management of refractory gastroparesis and GER post-LTx.

  View details for DOI 10.1055/a-1797-9587

  View details for PubMedID 35692909

• Development of a Preliminary Question Prompt List as a Communication Tool for Adults With Achalasia: A Modified Delphi Study. Journal of clinical gastroenterology Zhuo, J., Triadafilopoulos, G., Bredenoord, A. J., Clarke, J. O., Fass, R., Gyawali, C. P., Hawn, M., Hwang, J. H., Kahrilas, P. J., Katzka, D. A., Low, D., Massey, B. T., Patel, D., Penagini, R., Roman, S., Savarino, E., Smout, A. J., Swanstrom, L., Tatum, R., Vela, M. F., Zaninotto, G., Kamal, A. N. 2022

  Abstract

  BACKGROUND: Question prompt lists (QPLs) are structured sets of disease-specific questions that enhance patient-physician communication by encouraging patients to ask questions during consultations.AIM: The aim of this study was to develop a preliminary achalasia-specific QPL created by esophageal experts.METHODS: The QPL content was derived through a modified Delphi method consisting of 2 rounds. In round 1, experts provided 5 answers to the prompts "What general questions should patients ask when given a new diagnosis of achalasia" and "What questions do I not hear patients asking, but given my expertise, I believe they should be asking?" In round 2, experts rated questions on a 5-point Likert scale. Questions considered "essential" or "important" were accepted into the QPL. Feedback regarding the QPL was obtained in a pilot study wherein patients received the QPL before their consultation and completed surveys afterwards.RESULTS: Nineteen esophageal experts participated in both rounds. Of 148 questions from round 1, 124 (83.8%) were accepted into the QPL. These were further reduced to 56 questions to minimize redundancy. Questions were categorized into 6 themes: "What is achalasia," "Risks with achalasia," "Symptom management in achalasia," "Treatment of achalasia," "Risk of reflux after treatment," and "Follow-up after treatment." Nineteen patients participated in the pilot, most of whom agreed that the QPL was helpful (84.2%) and recommended its wider use (84.2%).CONCLUSIONS: This is the first QPL developed specifically for adults with achalasia. Although well-received in a small pilot, follow-up studies will incorporate additional patient feedback to further refine the QPL content and assess its usability, acceptability, and feasibility.

  View details for DOI 10.1097/MCG.0000000000001671

  View details for PubMedID 35180150

• Traction wire endoscopic submucosal dissection: tips and techniques from 4 institutions. VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy Bhatt, A., Hwang, J. H., Sharma, N. R., Waxman, I. 1800; 7 (1): 21-22

  Abstract

  Video 1Video presentation of traction wire endoscopic submucosal dissection: tips and techniques from 4 institutions.

  View details for DOI 10.1016/j.vgie.2021.08.011

  View details for PubMedID 35059534

• The risk of diffuse-type gastric cancer following diagnosis with gastric precancerous lesions: a systematic review and meta-analysis. Cancer causes & control : CCC Wang, J. E., Kim, S. E., Lee, B. E., Park, S., Hwang, J. H., Huang, R. J. 2021

  Abstract

  PURPOSE: Gastric cancers are classified as diffuse-type (DTGC) or intestinal-type (ITGC). DTGCs have distinct clinical and histopathologic features, and carry a worse overall prognosis compared to ITGCs. Atrophic gastritis (AG) and intestinal metaplasia (IM) are known precursors to ITGC. It is unknown if AG and IM increase risk for DTGC.METHODS: We performed a systematic review to identify studies reporting on the association of AG/IM and DTGC. We extracted the odds ratio (OR) of the association from studies, and performed pool analysis. Subgroup analysis was performed on studies reporting histologic severity (using operative link systems) to assess if histologic severity of AG/IM was associated with higher risk.RESULTS: We identified six case-control and eight cohort studies for inclusion. Both AG (pooled OR=1.9, 95% CI 1.5 to 2.4, p<0.001) and IM (pooled OR=2.3, 95% CI 1.9 to 2.9, p<0.001) demonstrated an association with DTGC. High AG severity was associated with increased risk for DTGC compared to low AG severity (OR=1.7, 95% CI 1.2 to 2.3, p=0.002). Similarly, high IM severity was associated with increased risk compared to low IM severity (OR=1.9, 95% CI 1.3 to 2.7, p=0.001).CONCLUSION: Both AG and IM are associated with DTGC. Increasing histologic severity of both AG and IM increases risk for DTGC. There may exist a common pathway between ITGC and some DTGCs mediated through mucosal precursor lesions. These data may inform future strategies of cancer risk attenuation and control.

  View details for DOI 10.1007/s10552-021-01522-1

  View details for PubMedID 34797436

• High-resolution photoacoustic/ultrasound imaging of the porcine stomach wall: an ex vivo feasibility study BIOMEDICAL OPTICS EXPRESS Kim, J., Ahn, J., Kang, G., Ha Hwang, J., Kim, C. 2021; 12 (11): 6717-6729

  View details for DOI 10.1364/BOE.441241

  View details for Web of Science ID 000714969300003

• High-resolution photoacoustic/ultrasound imaging of the porcine stomach wall: an ex vivo feasibility study. Biomedical optics express Kim, J., Ahn, J., Kang, G., Hwang, J. H., Kim, C. 2021; 12 (11): 6717-6729

  Abstract

  Photoacoustic (PA) imaging has become invaluable in preclinical and clinical research. Endoscopic PA imaging in particular has been explored as a noninvasive imaging modality to view vasculature and diagnose cancers in the digestive system. However, these feasibility studies are still limited to rodents or rabbits. Here, we develop a fully synchronized simultaneous ultrasound and photoacoustic microscopy system using two spectral bands (i.e., the visible and near-infrared) in both optical- and acoustic-resolution modes. We investigate the feasibility of imaging gastric vasculature in an ex vivo porcine model. The entire gastric wall, including the mucosa, submucosa, muscularis propria, and serosa, was excised from fresh porcine stomachs immediately followed by ultrasound and PA imaging being performed within a few hours of sacrifice. PA images of the mucosal vasculature were obtained at depths of 1.90 mm, which is a clinically significant accomplishment considering that the average thickness of the human mucosa is 1.26 mm. The layer structure of the stomach wall could be clearly distinguished in the overlaid PA and US images. Because gastric cancer starts from the mucosal surface and infiltrates into the submucosa, PA imaging can cover a clinically relevant depth in early gastric cancer diagnosis. We were able to detect mucosal vasculature in the entire mucosal layer, suggesting the potential utility of combined PA/US imaging in gastroenterology.

  View details for DOI 10.1364/BOE.441241

  View details for PubMedID 34858676

  View details for PubMedCentralID PMC8606154

• AGA Clinical Practice Update on Surveillance After Pathologically Curative Endoscopic Submucosal Dissection of Early Gastrointestinal Neoplasia in the United States: Commentary. Gastroenterology Wang, A. Y., Hwang, J. H., Bhatt, A., Draganov, P. V. 2021

  Abstract

  The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update was to review the available evidence and provide expert advice regarding surveillance using endoscopy and other relevant modalities after removal of dysplastic lesions and early gastrointestinal cancers with endoscopic submucosal dissection deemed to be pathologically curative. This Clinical Practice Update was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the Clinical Practice Updates Committee and external peer review through standard procedures of Gastroenterology. This expert commentary incorporates important as well as recently published studies in this field, and it reflects the experiences of the authors, who are advanced endoscopists with high-level expertise in performing endoscopic submucosal dissection to treat dysplasia and early cancers in the luminal gastrointestinal tract.

  View details for DOI 10.1053/j.gastro.2021.08.058

  View details for PubMedID 34689964

• Gastric Peroral Endoscopic Myotomy (GPOEM) Improves Symptoms and Need for Hospital Admission for Gastroparesis and Lung Transplant Patients Li, A., Ofosu, A., Kim, W., Podboy, A., Esquivel, M., Hwang, J. LIPPINCOTT WILLIAMS & WILKINS. 2021: S466-S467

  View details for Web of Science ID 000717526101452

• Use of the Rigidizing Overtube in Assisting Endoscopic Submucosal Dissection Among Patients With Ulcerative Colitis Wei, M. T., Hwang, J., Friedland, S. LIPPINCOTT WILLIAMS & WILKINS. 2021: S880

  View details for Web of Science ID 000717526103439

• Predicting Histological Diagnosis After Endoscopic Submucosal Dissection With Demographic Characteristics and Endoscopic Lesion Characteristics: An Analysis of a Large Cohort in North America Gudenkauf, F., Ferri, L., Aihara, H., Draganov, P., Yang, D., Jue, T., Munroe, C., Bhatt, A., Kumta, N. A., Othman, M., Aadam, A., Siegel, A., Grimm, I., DeWitt, J., Schlachterman, A., Kowalski, T. E., Samarasena, J., Chang, K., Su, B., Ujiki, M., Sharaiha, R., Carr-Locke, D. L., Tomizawa, Y., von Renteln, D., Bechara, R., Karasik, M., Patel, N., Fukami, N., Nishimura, M., Hanada, Y., Song, L., Laszkowska, M., Wang, A., Hwang, J., Friedland, S., Sethi, A., Ngamruengphong, S., Gastric ESD Study Grp LIPPINCOTT WILLIAMS & WILKINS. 2021: S496

  View details for Web of Science ID 000717526102047

• Impact of Race and Ethnicity on Risks of Cardia and Non-Cardia Gastric Adenocarcinomas in the US, 2000-2019: A Large Single-Center Retrospective Cohort Study Kim, S., Hwang, J., Huang, R. J., Kwon, S., Park, S., Choi, C., Lee, B. LIPPINCOTT WILLIAMS & WILKINS. 2021: S635

  View details for Web of Science ID 000717526102381

• Endoscopic Strictureplasty and Stent Placement for a Recalcitrant Esophageal Peptic Stricture Li, A., Hwang, J. LIPPINCOTT WILLIAMS & WILKINS. 2021: S875

  View details for Web of Science ID 000717526103420

• Diverging Patterns of Cardia and Non-Cardia Gastric Adenocarcinoma Incidence by Race and Age in the United States From 2000-2018 Kim, S., Huang, R. J., Hwang, J. LIPPINCOTT WILLIAMS & WILKINS. 2021: S635-S636

  View details for Web of Science ID 000717526102382

• Peroral Endoscopic Myotomy for Achalasia Subtypes and Esophagogastric Outflow Obstruction: Clinical Success and GERD Li, A., Podboy, A., Kim, W., Esquivel, M., Hwang, J. LIPPINCOTT WILLIAMS & WILKINS. 2021: S467

  View details for Web of Science ID 000717526101453

• Safety and efficacy of a novel resection system for direct endoscopic necrosectomy of walled-off pancreas necrosis: a prospective, international, multicenter trial. Gastrointestinal endoscopy Stassen, P. M., de Jonge, P. J., Bruno, M. J., Koch, A. D., Trindade, A. J., Benias, P. C., Sejpal, D. V., Siddiqui, U. D., Chapman, C. G., Villa, E., Tharian, B., Inamdar, S., Hwang, J. H., Barakat, M. T., Andalib, I., Gaidhane, M., Sarkar, A., Shahid, H., Tyberg, A., Binmoeller, K., Watson, R. R., Nett, A., Schlag, C., Abdelhafez, M., Friedrich-Rust, M., Schlachterman, A., Chiang, A. L., Loren, D., Kowalski, T., Kahaleh, M. 2021

  Abstract

  BACKGROUND AND AIMS: Direct endoscopic necrosectomy (DEN) of walled-off pancreatic necrosis (WOPN) lacks dedicated instruments and require repetitive and cumbersome procedures. This study evaluated the safety and efficacy of a new powered endoscopic debridement (PED) system designed to simultaneously resect and remove solid debris within WOPN.METHODS: This was a single-arm, prospective, multicenter, international device trial conducted from November 2018 to August 2019 at 10 sites. Patients with WOPN ≥6 cm and ≤22 cm, with >30% solid debris were enrolled. The primary endpoint was safety through 21 days after the last DEN procedure. Efficacy outcomes included clearance of necrosis, procedural time, adequacy of debridement, number of procedures until resolution, hospital stay duration, and quality of life.RESULTS: Thirty patients (mean age 55 years, 60% male) underwent DEN with no device-related adverse events. Fifteen out of 30 (50%) achieved complete debridement in 1 session, and 20 out of 30 (67%) achieved complete debridement within 2 or fewer sessions. A median of 1.5 interventions (range 1-7) were required. Median hospital stay was 10 days (IQR 22). There was an overall reduction of 91% in percent necrosis within WOPN from baseline to follow-up and 85% in collection volume. Baseline WOPN volume was positively correlated to total number of interventions (rho=0.363, p=0.049).CONCLUSION: The new PED system seems to be a safe and effective treatment tool for WOPN resulting in fewer interventions and lower hospital duration when compared with published data on using conventional instruments. Randomized controlled trials comparing the PED system with conventional DEN are needed.

  View details for DOI 10.1016/j.gie.2021.09.025

  View details for PubMedID 34562471

• EUS-guided cholecystoduodenostomy and ERCP in a patient with surgically altered anatomy with a double-balloon endoluminal interventional platform. VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy Li, A. A., Ofosu, A., Hwang, J. H. 2021; 6 (8): 368-371

  Abstract

  Video 1EUS-guided cholecystoduodenostomy and ERCP in a patient with surgically altered anatomy with a double-balloon endoluminal interventional platform.

  View details for DOI 10.1016/j.vgie.2021.04.010

  View details for PubMedID 34401634

• Endoscopic Submucosal Dissection In The West - Making Progress Toward A Promising Future. Gastroenterology Tomizawa, Y., Hwang, J. H. 2021

  View details for DOI 10.1053/j.gastro.2021.07.017

  View details for PubMedID 34280384

• Reply to Letter to the Editor. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Huang, R., Hwang, J. H. 2021

  View details for DOI 10.1016/j.cgh.2021.03.010

  View details for PubMedID 33716138

• Pepsinogens and Gastrin Demonstrate Low Discrimination for Gastric Precancerous Lesions in a Multi-Ethnic United States Cohort. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Huang, R. n., Park, S. n., Shen, J. n., Longacre, T. n., Ji, H. n., Hwang, J. H. 2021

  View details for DOI 10.1016/j.cgh.2021.01.009

  View details for PubMedID 33434656

• Utilization of Magnesium in Opioid-Free Anesthesia for Peroral Endoscopic Myotomy: A Case Report. A&A practice Kim, R. K., Hwang, J. H., Tsui, B. C. 2021; 15 (1): e01372

  Abstract

  Optimal anesthetic management has not been studied for peroral endoscopic myotomy (POEM). This case report documents 2 patients with esophageal motility disorders who underwent POEM with opioid-free, magnesium-based anesthesia. Both patients had no postoperative esophageal complications nor need for opioid therapy. We further describe the therapeutic potential of magnesium for management of esophageal pain.

  View details for DOI 10.1213/XAA.0000000000001372

  View details for PubMedID 33449540

• Use of a rigidizing overtube for altered-anatomy ERCP. VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy Wei, M. T., Friedland, S., Watson, R. R., Hwang, J. H. 2020; 5 (12): 664–66

  View details for DOI 10.1016/j.vgie.2020.08.003

  View details for PubMedID 33319136

• Use of a rigidizing overtube to complete an incomplete colonoscopy. VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy Wei, M. T., Hwang, J. H., Watson, R., Friedland, S. 2020; 5 (11): 583–85

  View details for DOI 10.1016/j.vgie.2020.06.014

  View details for PubMedID 33204926

• GIE Editorial Board top 10 topics: advances in GI endoscopy in2019. Gastrointestinal endoscopy Hwang, J. H., Jamidar, P., Kyanam Kabir Baig, K. R., Leung, F. W., Lightdale, J. R., Maranki, J. L., Okolo, P. I., Swanstrom, L. L., Chak, A. 2020; 92 (2): 241–51

  Abstract

  The American Society for Gastrointestinal Endoscopy's GIE Editorial Board reviewed original endoscopy-related articles published during 2019 in Gastrointestinal Endoscopy and 10 other leading medical and gastroenterology journals. Votes from each individual member were tallied to identify a consensus list of 10 topic areas of major advances in GI endoscopy. Individual board members summarized important findings published in these 10 areas of disinfection, artificial intelligence, bariatric endoscopy, adenoma detection, polypectomy, novel imaging, Barrett's esophagus, third space endoscopy, interventional EUS, and training. This document summarizes these "top 10" endoscopic advances of2019.

  View details for DOI 10.1016/j.gie.2020.05.021

  View details for PubMedID 32470427

• Do we need contrast agents for EUS? Endoscopic ultrasound Saftoiu, A., Napoleon, B., Arcidiacono, P. G., Braden, B., Burmeister, S., Carrara, S., Cui, X. W., Fusaroli, P., Gottschalk, U., Hocke, M., Hollerbach, S., Iglesias-Garcia, J., Jenssen, C., Kitano, M., Larghi, A., Oppong, K. W., Sahai, A. V., Sun, S., Burmester, E., Di Leo, M., Petrone, M. C., Santos, E., Teoh, A. Y., Hwang, J. H., Rimbas, M., Sharma, M., Puri, R., Kahaleh, M., Dietrich, C. F. 2020

  Abstract

  We recently introduced a series of articles that dealt with controversies in EUS. In Part I, the authors discussed which clinical information is necessary prior to EUS and whether other imaging modalities are required before embarking on EUS examinations. Part II focuses on technical details and controversies about the use of EUS in special situations. In this article, important practical issues regarding the application of contrast-enhanced EUS in various clinical settings are raised and controversially discussed from different points of view.

  View details for DOI 10.4103/eus.eus_20_20

  View details for PubMedID 32675463

• Do we need elastography for EUS? Endoscopic ultrasound Dietrich, C. F., Burmeister, S., Hollerbach, S., Arcidiacono, P. G., Braden, B., Fusaroli, P., Hocke, M., Iglesias-Garcia, J., Kitano, M., Larghi, A., Napoleon, B., Oppong, K. W., Rimbas, M., Saftoiu, A., Sahai, A. V., Sun, S., Dong, Y., Carrara, S., Hwang, J. H., Jenssen, C. 2020

  Abstract

  We recently introduced a series of papers "What should be known prior to performing EUS exams." In Part I, the authors discussed which clinical information and whether other imaging modalities are needed before embarking EUS examinations. In Part II, technical controversies on how EUS is performed were discussed from different points of view. In this article, important practical issues regarding EUS elastography will be raised and controversially discussed from very different points of view.

  View details for DOI 10.4103/eus.eus_25_20

  View details for PubMedID 32675464

• Increased tumour burden alters skeletal muscle properties in the KPC mouse model of pancreatic cancer. JCSM rapid communications Vohra, R., Campbell, M. D., Park, J., Whang, S., Gravelle, K., Wang, Y., Hwang, J., Marcinek, D. J., Lee, D. 2020; 3 (2): 44–55

  Abstract

  Background: Cancer cachexia is a multifactorial wasting syndrome that is characterized by the loss of skeletal muscle mass and weakness, which compromises physical function, reduces quality of life, and ultimately can lead to mortality. Experimental models of cancer cachexia have recapitulated this skeletal muscle atrophy and consequent decline in muscle force generating capacity. We address these issues in a novel transgenic mouse model Kras, Trp53 and Pdx-1-Cre (KPC) of pancreatic ductal adenocarcinoma (PDA) using multi-parametric magnetic resonance (mp-MR) measures.Methods: KPC mice (n = 10) were divided equally into two groups (n = 5/group) depending on the size of the tumor i.e. tumor size <250 mm3 and >250 mm3. Using mp-MR measures, we demonstrated the changes in the gastrocnemius muscle at the microstructural level. In addition, we evaluated skeletal muscle contractile function in KPC mice using an in vivo approach.Results: Increase in tumor size resulted in decrease in gastrocnemius maximum cross sectional area, decrease in T2 relaxation time, increase in magnetization transfer ratio, decrease in mean diffusivity, and decrease in radial diffusivity of water across the muscle fibers. Finally, we detected significant decrease in absolute and specific force production of gastrocnemius muscle with increase in tumor size.Conclusions: Our findings indicate that increase in tumor size may cause alterations in structural and functional parameters of skeletal muscles and that MR parameters may be used as sensitive biomarkers to noninvasively detect structural changes in cachectic muscles.

  View details for DOI 10.1002/rco2.13

  View details for PubMedID 33073264

• Efficacy of Endoscopic Submucosal Dissection for Superficial Gastric Neoplasia in a Large Cohort in North America. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Ngamruengphong, S., Ferri, L., Aihara, H., Draganov, P. V., Yang, D. J., Perbtani, Y. B., Jue, T. L., Munroe, C. A., Boparai, E. S., Mehta, N. A., Bhatt, A., Kumta, N. A., Othman, M. O., Mercado, M., Javaid, H., Aadam, A. A., Siegel, A., James, T. W., Grimm, I. S., DeWitt, J. M., Novikov, A., Schlachterman, A., Kowalski, T., Samarasena, J., Hashimoto, R., El Hage Chehade, N., Lee, J., Chang, K., Su, B., Ujiki, M. B., Mehta, A., Sharaiha, R. Z., Carr-Locke, D. L., Chen, A., Chen, M., Chen, Y., Khoshknab, M. P., Wang, R., Kerdsirichairat, T., Tomizawa, Y., von Renteln, D., Kumbhari, V., Khashab, M. A., Bechara, R., Karasik, M., Patel, N. J., Fukami, N., Nishimura, M., Hanada, Y., Wong Kee Song, L. M., Laszkowska, M., Wang, A. Y., Hwang, J. H., Friedland, S., Sethi, A., Kalloo, A. N. 2020

  Abstract

  BACKGROUND & AIMS: Endoscopic submucosal dissection (ESD) is a widely accepted treatment option for superficial gastric neoplasia in Asia, but there are few data on outcomes of gastric ESD from North America. We aimed to evaluate the safety and efficacy of gastric ESD in North America.METHODS: We analyzed data from 347 patients who underwent gastric ESD at 25 centers, from 2010 through 2019. We collected data on patient demographics, lesion characteristics, procedure details and related adverse events, treatment outcomes, local recurrence, and vital status at the last follow up. For the 277 patients with available follow-up data, the median interval between initial ESD and last clinical or endoscopic evaluation was 364 days. The primary endpoint was the rate of en bloc and R0 resection. Secondary outcomes included curative resection, rates of adverse events and recurrence, and gastric cancer-related death.RESULTS: Ninety patients (26%) had low-grade adenomas or dysplasia, 82 patients (24%) had high-grade dysplasia, 139 patients (40%) had early gastric cancer, and 36 patients (10%) had neuroendocrine tumors. Proportions of en bloc and R0 resection for all lesions were 92%/82%, for early gastric cancers were 94%/75%, for adenomas and low-grade dysplasia were 93%/ 92%, for high-grade dysplasia were 89%/ 87%, and for neuroendocrine tumors were 92%/75%. Intraprocedural perforation occurred in 6.6% of patients; 82% of these were treated successfully with endoscopic therapy. Delayed bleeding occurred in 2.6% of patients. No delayed perforation or procedure-related deaths were observed. There were local recurrences in 3.9% of cases; all occurred after non-curative ESD resection. Metachronous lesions were identified in 14 patients (6.9%). One of 277 patients with clinical follow up died of metachronous gastric cancer that occurred 2.5 years after the initial ESD.CONCLUSIONS: ESD is a highly effective treatment for superficial gastric neoplasia and should be considered as a viable option for patients in North America. The risk of local recurrence is low and occurs exclusively after non-curative resection. Careful endoscopic surveillance is necessary to identify and treat metachronous lesions.

  View details for DOI 10.1016/j.cgh.2020.06.023

  View details for PubMedID 32565290

• NOVEL RIGIDIZING OVERTUBE FOR ENTEROSCOPE/COLONOSCOPE STABILIZATION AND LOOP PREVENTION Friedland, S., Watson, R. R., Hwang, J. MOSBY-ELSEVIER. 2020: AB238–AB239

  View details for Web of Science ID 000545678400474

• Regional disparities in gastric cancer survival in the United States: An observational cohort study of the Surveillance Epidemiology and End Results Program, 2004-2016 Huang, R., Hsing, A., Palaniappan, L., Hwang, J. AMER ASSOC CANCER RESEARCH. 2020

  View details for DOI 10.1158/1538-7755.DISP19-C058

  View details for Web of Science ID 000580647800292

• Disaggregation of gastric cancer risk Between Asian American subgroups Huang, R. J., Hwang, J., Hsing, A., Palaniappan, L. AMER ASSOC CANCER RESEARCH. 2020

  View details for DOI 10.1158/1538-7755.DISP19-PR03

  View details for Web of Science ID 000580647800524

• COMPARISON OF EUS-GUIDED, ENDOSCOPIC TRANSPAPILLARY AND PERCUTANEOUS GALLBLADDER DRAINAGE FOR ACUTE CHOLECYSTITIS: A SYSTEMATIC REVIEW AND NETWORK METANALYSIS Podboy, A. J., Yuan, J. J., Stave, C. D., Chan, S. M., Hwang, J., Teoh, A. Y. MOSBY-ELSEVIER. 2020: AB309

  View details for Web of Science ID 000545678400617

• PROBE-BASED CONFOCAL LASER ENDOMICROSCOPY (P-CLE) IS USEFUL AS AN ALTERNATIVE "OPTICAL" BIOPSY MODALITY IN DIAGNOSIS OF GASTRIC INTESTINAL METAPLASIA (GIM) IN US POPULATION Tomizawa, Y., Hwang, J., Baxi, A., Balmadrid, B. L., Abe, S., Saito, Y., Inadomi, J. M., Strate, L. L. MOSBY-ELSEVIER. 2020: AB587

  View details for Web of Science ID 000545678401316

• GASTRIC PERORAL ENDOSCOPIC MYOTOMY COMPARED TO SURGICAL PYLOROMYOTOMY IN THE TREATMENT OF GASTROPARESIS: A CASE-MATCHED MULTICENTER STUDY AbiMansour, J. P., Meybodi, M., Ichkhanian, Y., Wong, H., Ujiki, M., Podboy, A. J., Hwang, J., Deshmukh, A. A., Nieto, J., Pawa, R., Koch, K. L., Pawa, S., Chung, C., Schlachterman, A., Kowalski, T. E., Batra, V., Kumta, N. A., Khashab, M. A. MOSBY-ELSEVIER. 2020: AB6

  View details for Web of Science ID 000545678400010

• PROSPECTIVE TRIAL EVALUATING THE SAFETY AND EFFECTIVENESS OF THE INTERSCOPE ENDOROTOR (R) RESECTION SYSTEM FOR DIRECT ENDOSCOPIC NECROSECTOMY OF WALLED-OF PANCREATIC NECROSIS (ENDOROTOR DEN TRIAL) Stassen, P. M., de Jonge, P. F., Koch, A. D., Bruno, M. J., Trindade, A., Benias, P. C., Sejpal, D. V., Siddiqui, U. D., Chapman, C. G., Villa, E., Tharian, B., Inamdar, S., Hwang, J., Barakat, M., Andalib, I., Gaidhane, M., Sarkar, A., Shahid, H. M., Tyberg, A., Binmoeller, K. F., Watson, R. R., Nett, A., Schlag, C., Abdelhafez, M., Friedrich-Rust, M., Schlachterman, A., Chiang, A., Loren, D. E., Kowalski, T. E., Kahaleh, M. MOSBY-ELSEVIER. 2020: AB80–AB81

  View details for Web of Science ID 000545678400149

• County Rurality and Socioeconomic Deprivation is Associated with Reduced Survival from Gastric Cancer in the United States. Gastroenterology Huang, R. J., Shah, S. C., Camargo, M. C., Palaniappan, L., Hwang, J. H. 2020

  View details for DOI 10.1053/j.gastro.2020.05.006

  View details for PubMedID 32387539

• The Management of Gastric Intestinal Metaplasia in the United States - A Controversial Topic. Gastroenterology Huang, R. J., Hwang, J. H. 2020

  View details for DOI 10.1053/j.gastro.2020.02.066

  View details for PubMedID 32234304

• Long-term outcomes of per-oral endoscopic myotomy compared to laparoscopic Heller myotomy for achalasia: a single-center experience. Surgical endoscopy Podboy, A. J., Hwang, J. H., Rivas, H., Azagury, D., Hawn, M., Lau, J., Kamal, A., Friedland, S., Triadafilopoulos, G., Zikos, T., Clarke, J. O. 2020

  Abstract

  INTRODUCTION: Many centers have reported excellent short-term efficacy of per-oral endoscopic myotomy (POEM) for the treatment of achalasia. However, long-term data are limited and there are few studies comparing the efficacy of POEM versus Heller Myotomy (HM).AIMS: To compare the long-term clinical efficacy of POEM versus HM.METHODS: Using a retrospective, parallel cohort design, all cases of POEM or HM for achalasia between 2010 and 2015 were assessed. Clinical failure was defined as (a) Eckardt Score>3 for at least 4weeks, (b) achalasia-related hospitalization, or (c) repeat intervention. All index manometries were classified via Chicago Classification v3. Pre-procedural clinical, manometric, radiographic data, and procedural data were reviewed.RESULTS: 98 patients were identified (55 POEM, 43 Heller) with mean follow-up of 3.94years, and 5.44years, respectively. 83.7% of HM patients underwent associated anti-reflux wrap (Toupet or Dor). Baseline clinical, demographic, radiographic, and manometric data were similar between the groups. There was no statistical difference in overall long-term success (POEM 72.7%, HM 65.1% p=0.417, although higher rates of success were seen in Type III Achalasia in POEM vs Heller (53.3% vs 44.4%, p<0.05). Type III Achalasia was the only variable associated with failure on a univariate COX analysis and no covariants were identified on a multivariate Cox regression. There was no statistical difference in GERD symptoms, esophagitis, or major procedural complications.CONCLUSION: POEM and HM have similar long-term (4-year) efficacy with similar adverse event and reflux rates. POEM was associated with greater efficacy in Type III Achalasia.

  View details for DOI 10.1007/s00464-020-07450-6

  View details for PubMedID 32157405

• Magnetic resonance imaging biomarkers for pulsed focused ultrasound treatment of pancreatic ductal adenocarcinoma. World journal of gastroenterology Maloney, E., Wang, Y., Vohra, R., Son, H., Whang, S., Khokhlova, T., Park, J., Gravelle, K., Totten, S., Hwang, J. H., Lee, D. 2020; 26 (9): 904–17

  Abstract

  BACKGROUND: The robust fibroinflammatory stroma characteristic of pancreatic ductal adenocarcinoma (PDA) impedes effective drug delivery. Pulsed focused ultrasound (pFUS) can disrupt this stroma and has improved survival in an early clinical trial. Non-invasive methods to characterize pFUS treatment effects are desirable for advancement of this promising treatment modality in larger clinical trials.AIM: To identify promising, non-invasive pre-clinical imaging methods to characterize acute pFUS treatment effects for in vivo models of PDA.METHODS: We utilized quantitative magnetic resonance imaging methods at 14 tesla in three mouse models of PDA (subcutaneous, orthotopic and transgenic - KrasLSL-G12D/+ , Trp53LSL-R172H/+ , Cre or "KPC") to assess immediate tumor response to pFUS treatment (VIFU 2000 Alpinion Medical Systems; 475 W peak electric power, 1 ms pulse duration, 1 Hz, duty cycle 0.1%) vs sham therapy, and correlated our results with histochemical data. These pFUS treatment parameters were previously shown to enhance tumor permeability to chemotherapeutics. T1 and T2 relaxation maps, high (126, 180, 234, 340, 549) vs low (7, 47, 81) b-value apparent diffusion coefficient (ADC) maps, magnetization transfer ratio (MTR) maps, and chemical exchange saturation transfer (CEST) maps for the amide proton spectrum (3.5 parts per million or "ppm") and the glycosaminoglycan spectrum (0.5-1.5 ppm) were generated and analyzed pre-treatment, and immediately post-treatment, using ImageJ. Animals were sacrificed immediately following post-treatment imaging. The whole-tumor was selected as the region of interest for data analysis and subsequent statistical analysis. T-tests and Pearson correlation were used for statistical inference.RESULTS: Mean high-b value ADC measurements increased significantly with pFUS treatment for all models. Mean glycosaminoglycan CEST and T2 measurements decreased significantly post-treatment for the KPC group. Mean MTR and amide CEST values increased significantly for the KPC group. Hyaluronic acid focal intensities in the treated regions were significantly lower following pFUS treatment for all animal models. The magnetic resonance imaging changes observed acutely following pFUS therapy likely reflect: (1) Sequelae of variable degrees of microcapillary hemorrhage (T1, MTR and amide CEST); (2) Lower PDA glycosaminoglycan content and associated water content (glycosaminoglycan CEST, T2 and hyaluronic acid focal intensity); and (3) Improved tumor diffusivity (ADC) post pFUS treatment.CONCLUSION: T2, glycosaminoglycan CEST, and ADC maps may provide reliable quantitation of acute pFUS treatment effects for patients with PDA.

  View details for DOI 10.3748/wjg.v26.i9.904

  View details for PubMedID 32206002

• Comparison of EUS-guided endoscopic transpapillary and percutaneous gallbladder drainage for acute cholecystitis: a systematic review with network meta-analysis. Gastrointestinal endoscopy Podboy, A. n., Yuan, J. n., Stave, C. D., Chan, S. M., Hwang, J. n., Teoh, A. Y. 2020

  Abstract

  The optimal method of gallbladder drainage for acute cholecystitis in nonsurgical candidates is uncertain. The aim of the current study was to conduct a network meta-analysis comparing the 3 methods of gallbladder drainage (percutaneous, transpapillary, and EUS-guided).A comprehensive literature search for all comparative studies assessing the efficacy of either of the 2 or all of the modalities used for treatment of acute cholecystitis in patients that were at high risk for cholecystectomy was performed. Primary outcomes of technical and clinical success and postprocedure adverse events were assessed. Secondary outcomes include reintervention, unplanned readmissions, recurrent cholecystitis, and mortality.Ten studies were identified, comprising 1267 patients (472 EUS-GBD, 493 PT-GBD, 302 ETP-GBD). In the network ranking estimate, PT-GBD and EUS-GBD had highest likelihood of technical success (EUS-GBD vs PT-GBD vs ETP-GBD = 2.00 vs 1.02 vs 2.98) and clinical success (EUS-GBD vs PT-GBD vs ETP-GBD = 1.48 vs 1.55 vs 2.98). EUS-GBD had lowest risk of recurrent cholecystitis (EUS-GBD vs PT-GBD vs ETP-GBD = 1.089 vs 2.02 vs 2.891). PT-GBD has highest risk of reintervention (EUS-GBD vs PT-GBD vs ETP-GBD = 1.81 vs 2.99 vs 1.199) and unplanned readmissions (EUS-GBD vs PT-GBD vs ETP-GBD = 1.582 vs 2.944 vs 1.474) whereas ETP-GBD drainage was associated with lowest rates of mortality (EUS-GBD vs PT-GBD vs ETP-GBD = 2.62 vs 2.09 vs 1.29).The 3 modalities of gallbladder drainage have their respective advantages and disadvantages. Selection of the technique will depend on available expertise. In centers with expertise in endoscopic gallbladder drainage, the techniques are preferred over PT-GBD with improved outcomes.

  View details for DOI 10.1016/j.gie.2020.09.040

  View details for PubMedID 32987004

• Mucosal Incision-Assisted Endoscopic Biopsy as an Alternative to Endoscopic Ultrasound-Guided Fine-Needle Aspiration/Biopsy for Gastric Subepithelial Tumor. Clinical endoscopy Choi, C. W., Hwang, J. H. 2020; 53 (5): 505–7

  View details for DOI 10.5946/ce.2020.187

  View details for PubMedID 33027581

• Endoscopic submucosal dissection (ESD) for Barrett's esophagus (BE)-related early neoplasia after standard endoscopic management is feasible and safe. Endoscopy international open Tomizawa, Y. n., Friedland, S. n., Hwang, J. H. 2020; 8 (4): E498–E505

  Abstract

  Background and study aims  There is little data on the feasibility and safety of endoscopic submucosal dissection (ESD) as a salvage treatment for Barrett's esophagus (BE)-related neoplasia after standard endoscopic treatments. Patients and methods  A multicenter retrospective analysis on patients who underwent ESD for BE was performed. The primary endpoint was effectiveness of obtaining en-bloc resection in salvage as compared to non-salvage treatments. Results  Median age was 71 (IQR 55 - 79) years. Twelve (37%) of 32 patients underwent salvage ESD. Median resection time was 100 (IQR 60 - 136) minutes. En-bloc resection was achieved in 31 patients (97 %). Complete R0 resection was obtained in 75 % in the salvage group and 80 % in the non-salvage group ( P  = 1.00). In seven patients (22 %), the pre-ESD diagnosis was upgraded on post-ESD histopathology (1 low-grade dysplasia to high grade dysplasia [HGD], 4 HGD to early esophageal carcinoma (EAC), and 2 intramucosal EAC to invasive EAC). No perforations occurred in either group. Two late adverse events occurred, both in the salvage group ( P  = 0.133). Delayed bleeding occurred in a patient who had just resumed warfarin and stricture occurred in a patient who had a circumferential resection requiring serial dilation and stent placement. Conclusions  Our cohort study demonstrated that ESD as salvage therapy for BE related neoplasia is feasible and safe, achieving similar high rates of en-bloc resection and complete R0 resection as in treatment-naïve patients. Referral to an expert center performing ESD should be considered for patients with recurrence or progression following endoscopic mucosal resection or ablation therapy.

  View details for DOI 10.1055/a-0905-2465

  View details for PubMedID 32258371

  View details for PubMedCentralID PMC7089792

• Novel use of endoscopic morcellator to clear large obscuring clot in patient with upper-GI bleed. VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy Gubatan, J. n., Kwo, P. n., Hwang, J. H. 2020; 5 (2): 58–60

  View details for DOI 10.1016/j.vgie.2019.10.006

  View details for PubMedID 32051910

  View details for PubMedCentralID PMC7003128

• One Size Does Not Fit All: Marked Heterogeneity in Incidence of and Survival from Gastric Cancer among Asian American Subgroups. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology Huang, R. J., Sharp, N. n., Talamoa, R. O., Ji, H. P., Hwang, J. H., Palaniappan, L. P. 2020

  Abstract

  Asian Americans are at higher risk for non-cardia gastric cancers (NCGCs) relative to non-Hispanic Whites (NHWs). Asian Americans are genetically, linguistically, and culturally heterogeneous, yet have mostly been treated as a single population in prior studies. This aggregation may obscure important subgroup-specific cancer patterns.We utilized data from 13 regional United States cancer registries from 1990-2014 to determine secular trends in incidence and survivorship from NCGC. Data were analyzed for NHWs and the six largest Asian American subgroups: Chinese, Japanese, Filipino, Korean, Vietnamese, and South Asian (Indian/Pakistani).There exists substantial heterogeneity in NCGC incidence between Asian subgroups, with Koreans (48.6 per 100,000 person-years) having seven-fold higher age-adjusted incidence than South Asians (7.4 per 100,000 person-years). Asians had generally earlier stages of diagnosis and higher rates of surgical resection compared to NHWs. All Asian subgroups also demonstrated higher five-year observed survival compared to NHWs, with Koreans (41.3%) and South Asians (42.8%) having survival double that of NHWs (20.1%, p<0.001). In multivariable regression, differences in stage of diagnosis and rates of resection partially explained the difference in survivorship between Asian subgroups.We find substantial differences in incidence, staging, histology, treatment, and survivorship from NCGC between Asian subgroups, data which challenge our traditional perceptions about gastric cancer in Asians. Both biological heterogeneity and cultural/environmental differences may underlie these findings.These data are relevant to the national discourse regarding the appropriate role of gastric cancer screening, and identifies high-risk racial/ethnic subgroups who many benefit from customized risk attenuation programs.

  View details for DOI 10.1158/1055-9965.EPI-19-1482

  View details for PubMedID 32152216

• Novel rigidizing overtube for colonoscope stabilization and loop prevention (with video). Gastrointestinal endoscopy Wei, M. T., Hwang, J. H., Watson, R. R., Park, W. n., Friedland, S. n. 2020

  Abstract

  Loop formation can impede scope advancement, destabilize the tip and cause pain. Strategies to mitigate looping include torque-based reduction maneuvers, variable stiffness shafts and abdominal splinting. In some cases, these strategies are insufficient and there is need for novel instruments. Loop formation is of particular concern in colonoscopy, but it can also impact performance of other endoscopic procedures such as enteroscopy and altered-anatomy ERCP. In this case series we demonstrate the utility of a novel rigidizing overtube (Pathfinder, Neptune Medical, Burlingame, Calif, USA) in colonoscopy and other endoscopic procedures where loop management is critical.We describe our initial experience with the Pathfinder overtube in 29 patients. The overtube is 85 centimeters long and can accommodate a pediatric colonoscope. In its native state, the overtube is extremely flexible. Once the overtube is advanced to the desired location, application of a vacuum to the device causes the device to become 15 times stiffer. The endoscope can then be advanced through the overtube without loop formation in the region that the overtube traverses.The overtube was used in 29 patients to assist with difficult procedures. The patients were predominantly male (N=18; 62.1%), with median age 66 (interquartile range 57-72). One patient received an upper endoscopy (3.4%), 24 received colonoscopy (82.8%), and 4 received enteroscopy (13.8%). The overtube was used in 12 for incomplete colonoscopy (41.4%), 6 for depth (20.7%), and 11 for stability (37.9%). Colonoscopy was performed in the setting of screening (N=3), surveillance given polyp history (N=7), referrals for polyp removal (N=10), workup of iron deficiency anemia (N=2), and incomplete colonoscopy (N=1). The lower endoscopy cases had a median cecal intubation time of 5 minutes and had interquartile range (4.25 - 7 minutes). Enteroscopy was performed in 4 patients. (1) The distal 60 cm of the ileum was examined with a pediatric colonoscope to exclude ileitis. (2) The overtube was used to stabilize a 6 mm endoscope to traverse a tight Crohn's ileocolonic stricture. (3) Altered-anatomy ERCP was performed using an enteroscope through the overtube to reach a hepaticojejunostomy. (4) Upper enteroscopy was performed and the mid-jejunum was reached. We present 4 cases that demonstrate the use of the overtube. There were no adverse events.Initial experience with a novel rigidizing overtube suggests that this tool can be useful in colonoscopy and other endoscopic procedures that are affected by looping.

  View details for DOI 10.1016/j.gie.2020.07.054

  View details for PubMedID 32739483

• Novel Use of EndoRotor (R) Device to Clear Large Obscuring Clot in Patient With Upper Gastrointestinal Bleed Gubatan, J., Kwo, P., Hwang, J. LIPPINCOTT WILLIAMS & WILKINS. 2019: S1182

  View details for DOI 10.14309/01.ajg.0000598020.30095.76

  View details for Web of Science ID 000509756005089

• Disaggregation of Gastric Cancer Risk Between Asian American Subgroups Huang, R., Hwang, J., Palaniappan, L. LIPPINCOTT WILLIAMS & WILKINS. 2019: S688–S689

  View details for DOI 10.14309/01.ajg.0000594460.74476.13

  View details for Web of Science ID 000509756003035

• Variability in Gastric Cancer Survival by Disaggregated Asian American Subgroups Huang, R., Palaniappan, L., Hwang, J. LIPPINCOTT WILLIAMS & WILKINS. 2019: S689

  View details for Web of Science ID 000509756003036

• Risk Factors for Advanced Gastric Intestinal Metaplasia in a Multi-Ethnic United States Cohort Huang, R., Park, S., Chitre, T., Shen, J., Longacre, T., Hwang, J. LIPPINCOTT WILLIAMS & WILKINS. 2019: S689–S690

  View details for Web of Science ID 000509756003037

• Diagnosis and Management of Gastric Intestinal Metaplasia: Current Status and Future Directions. Gut and liver Huang, R. J., Choi, A. Y., Truong, C. D., Yeh, M. M., Hwang, J. H. 2019

  Abstract

  Gastric intestinal metaplasia (GIM) is a known premalignant condition of the human stomach along the pathway to gastric cancer (GC). Histologically, GIM represents the replacement of normal gastric mucosa by mucin-secreting intestinal mucosa. Helicobacter pylori infection is the most common etiologic agent of GIM development worldwide. The prevalence of GIM is heterogeneous among different regions of the world and correlates with the population endemicity of H. pylori carriage, among other environmental factors. GC remains the third leading cause of cancer-related mortality globally. GIM is usually diagnosed by upper endoscopy with biopsy, and histologic scoring systems have been developed to risk-stratify patients at highest risk for progression to GC. Several recent endoscopic imaging modalities may improve the optical detection of GIM and early GC. Appropriate surveillance of GIM may be cost effective and represents an opportunity for the early diagnosis and therapy of GC. Certain East Asian nations have established population-level programs for the screening and surveillance of GIM; guidelines regarding GIM surveillance have also recently been published in Europe. By contrast, few data exist regarding the appropriateness of surveillance of GIM in the United States. In this review, we discuss the pathogenesis, epidemiology, diagnosis, and management of GIM with an emphasis on the role of appropriate endoscopic surveillance.

  View details for DOI 10.5009/gnl19181

  View details for PubMedID 31394893

• Low Frequency of Lymph Node Metastases in Patients in the United States With Early-stage Gastric Cancers That Fulfill Japanese Endoscopic Resection Criteria CLINICAL GASTROENTEROLOGY AND HEPATOLOGY Hanada, Y., Choi, A. Y., Hwang, J., Draganov, P. V., Khanna, L., Sethi, A., Bartel, M. J., Goel, N., Abe, S., De Latour, R. A., Park, K., Melis, M., Newman, E., Hatzaras, I., Reddy, S. S., Farma, J. M., Liu, X., Schlachterman, A., Kresak, J., Trapp, G., Ansari, N., Schrope, B., Lee, J., Dhall, D., Lo, S., Jamil, L. H., Burch, M., Gaddam, S., Gong, Y., Del Portillo, A., Tomizawa, Y., Truong, C. D., Gutierrez, O., Montgomery, E., Johnston, F. M., Duncan, M., Canto, M., Ahuja, N., Lennon, A., Ngamruengphong, S. 2019; 17 (9): 1763–69

  View details for DOI 10.1016/j.cgh.2018.11.031

  View details for Web of Science ID 000476863400022

• Current Status of EUS in Gastrointestinal Subepithelial Tumors. Clinical endoscopy Kim, S. G., Song, J. H., Hwang, J. H. 2019

  Abstract

  Gastrointestinal subepithelial tumors (GSTs) are usually detected incidentally on endoscopic or radiologic examinations. In conventional endoscopy, a GST usually presents as a protuberant lesion with an intact mucosal surface. As the lesion is located beneath the mucosal layer of the gastrointestinal tract, conventional biopsy typically does not reveal the pathologic diagnosis. First, a GST should be differentiated from an extrinsic compression through the positional change of the patient during conventional endoscopic examination. In cases of GSTs originating from the gastrointestinal wall, endoscopic ultrasonography (EUS) can be beneficial for narrowing the differential diagnosis through delineation of echo findings and by determining the layer of origin. EUS findings can also help determine the management strategies for GSTs by making a differential diagnosis according to malignant potential.

  View details for DOI 10.5946/ce.2019.024

  View details for PubMedID 31286747

• Technical review of gastric per-oral endoscopic myotomy INTERNATIONAL JOURNAL OF GASTROINTESTINAL INTERVENTION Podboy, A., Hwang, J. 2019; 8 (3): 140–44

  View details for DOI 10.18528/ijgii190008

  View details for Web of Science ID 000521646200008

• Gastric per-oral endoscopic myotomy: Current status and future directions WORLD JOURNAL OF GASTROENTEROLOGY Podboy, A., Hwang, J., Nguyen, L. A., Garcia, P., Zikos, T. A., Kamal, A., Triadafilopoulos, G., Clarke, J. O. 2019; 25 (21): 2581–90

  View details for DOI 10.3748/wjg.v25.i21.2581

  View details for Web of Science ID 000470246400004

• Gastric per-oral endoscopic myotomy: Current status and future directions. World journal of gastroenterology Podboy, A., Hwang, J. H., Nguyen, L. A., Garcia, P., Zikos, T. A., Kamal, A., Triadafilopoulos, G., Clarke, J. O. 2019; 25 (21): 2581-2590

  Abstract

  Gastroparesis, or symptomatic delayed gastric emptying in the absence of mechanical obstruction, is a challenging and increasingly identified syndrome. Medical options are limited and the only medication approved by the Food and Drug Administration for treatment of gastroparesis is metoclopramide, although other agents are frequently used off label. With this caveat, first-line treatments for gastroparesis include dietary modifications, antiemetics and promotility agents, although these therapies are limited by suboptimal efficacy and significant medication side effects. Treatment of patients that fail first-line treatments represents a significant therapeutic challenge. Recent advances in endoscopic techniques have led to the development of a promising novel endoscopic therapy for gastroparesis via endoscopic pyloromyotomy, also referred to as gastric per-oral endoscopic myotomy or per-oral endoscopic pyloromyotomy. The aim of this article is to review the technical aspects of the per-oral endoscopic myotomy procedure for the treatment of gastroparesis, provide an overview of the currently published literature, and outline potential next directions for the field.

  View details for DOI 10.3748/wjg.v25.i21.2581

  View details for PubMedID 31210711

  View details for PubMedCentralID PMC6558440

• ENDOSCOPIC SUBMUCOSAL DISSECTION FOR GASTRIC NEOPLASIA: A LARGE MULTICENTER STUDY FROM NORTH AMERICA Ngamruengphong, S., Ferri, L. E., Aihara, H., Draganov, P. V., Yang, D., Perbtani, Y. B., Hanada, Y., Song, L., Kumta, N. A., Othman, M. O., Mercado, M. O., Javaid, H., Aadam, A., Siegel, A. B., James, T. W., Grimm, I. S., DeWitt, J. M., Novikov, A. A., Schlachterman, A., Kowalski, T. E., Samarasena, J. B., Hashimoto, R., Chehade, N. E., Lee, J., Chang, K. J., Su, B., Chen, A., Chen, M., Chen, Y., Ujiki, M., Mehta, A., Sharaiha, R. Z., Carr-Locke, D. L., Kumbhari, V., Khashab, M. A., Khoshknab, M., Wang, R., Kerdsirichairat, T., Tomizawa, Y., von Renteln, D., Bechara, R., Patel, N. J., Fukami, N., Lazkowska, M., Sethi, A., Wang, A. Y., Hwang, J., Friedland, S., Kalloo, A. N. MOSBY-ELSEVIER. 2019: AB102–AB103

  View details for Web of Science ID 000470094900099

• OUTCOMES OF ENDOSCOPIC SUBMUCOSAL DISSECTION VERSUS SURGERY IN EARLY GASTRIC CANCER MEETING STANDARD AND EXPANDED INDICATIONS: A MULTICENTER NORTH AMERICAN COHORT Kerdsirichairat, T., Wang, R., Aihara, H., Draganov, P. V., Kumta, N. A., Tomizawa, Y., Truong, C. D., Lo, S. K., Jamil, L. H., Gaddam, S., Burch, M., Dhall, D., Perbtani, Y. B., Yang, D., Bartel, M. J., Goel, N., Reddy, S. S., Farma, J. M., Gong, Y., Ferri, L. E., Chen, A., Chen, M., Chen, Y., Sethi, A., Ansari, N., Trapp, G., Schrope, B., Del Portillo, A., DeLatour, R., Park, K. H., Khanna, L. G., Melis, M., Newman, E., Hatzaras, I., James, T. W., Grimm, I. S., DeWitt, J. M., Siegel, A. B., Aadam, A., Wang, A. Y., Bechara, R., Abe, S., Song, L., Gutierrez, O., Montgomery, E., Johnston, F. M., Duncan, M. D., Canto, M. I., Lennon, A., Hanada, Y., Hwang, J., Friedland, S., Ngamruengphong, S. MOSBY-ELSEVIER. 2019: AB350–AB351

  View details for Web of Science ID 000470094901340

• PER-ORAL ENDOSCOPIC MYOTOMY HAS SIMILAR EFFICACY COMPARED TO LAPAROSCOPIC HELLER MYOTOMY AFTER 4 YEARS: A SINGLE CENTER EXPERIENCE Podboy, A. J., Hwang, J., Rivas, H., Azagury, D., Hawn, M. T., Kamal, A., Triadafilopoulos, G., Zikos, T., Clarke, J. O. MOSBY-ELSEVIER. 2019: AB201–AB202

  View details for Web of Science ID 000470094901010

• PROPHYLACTIC ENDOSCOPIC CLOSURE DOES NOT REDUCE ADVERSE EVENTS FOLLOWING ENDOSCOPIC SUBMUCOSAL DISSECTION: A CASE-MATCHED MULTICENTER STUDY Mehta, A., Ngamruengphong, S., Hajifathalian, K., Shah, S. L., Dawod, E., Ferri, L. E., Aihara, H., Song, L., Hanada, Y., Kumta, N. A., Aadam, A., Siegel, A. B., James, T. W., Grimm, I. S., Novikov, A. A., Kumbhari, V., Tomizawa, Y., von Renteln, D., Bechara, R., Hwang, J., Friedland, S., Kalloo, A. N., Nieto, J., Othman, M. O., Sampath, K., Mahadev, S., Mukewar, S., Carr-Locke, D. L., Khashab, M. A., Sharaiha, R. Z. MOSBY-ELSEVIER. 2019: AB97

  View details for Web of Science ID 000470094900090

• A Chance to Cut Is a Chance to Cure: Endoscopic Submucosal Dissection for Early Gastric Cancer DIGESTIVE DISEASES AND SCIENCES Huang, R. J., Charville, G. W., Hwang, J., Friedland, S. 2019; 64 (5): 1129–32

  View details for DOI 10.1007/s10620-018-5317-8

  View details for Web of Science ID 000466886100013

• How to decrease the risk of perforation in endoscopic submucosal dissection (ESD) TECHNIQUES IN GASTROINTESTINAL ENDOSCOPY Kim, S., Hwang, J. 2019; 21 (2): 99–103

  View details for DOI 10.1016/j.tgie.2019.05.001

  View details for Web of Science ID 000471019800007

• Routine gastric biopsies: Should we be doing more? Gastrointestinal endoscopy Huang, R. J., Hwang, J. H. 2019; 89 (6): 1150–51

  View details for DOI 10.1016/j.gie.2019.02.010

  View details for PubMedID 31104747

• Boiling Histotripsy Ablation of Renal Cell Carcinoma in the Eker Rat Promotes a Systemic Inflammatory Response. Ultrasound in medicine & biology Schade, G. R., Wang, Y. N., D'Andrea, S. n., Hwang, J. H., Liles, W. C., Khokhlova, T. D. 2019; 45 (1): 137–47

  Abstract

  Boiling histotripsy (BH) is an experimental focused ultrasound technique that produces non-thermal mechanical ablation. We evaluated the feasibility, short-term histologic effects and the resulting acute inflammatory response to BH ablation of renal cell carcinoma (RCC) in the Eker rat. Genotyped Eker rats were monitored for de novo RCCs with serial ultrasound (US) imaging. When tumors were ≥8 mm, rats underwent ultrasound-guided extracorporeal ablation of the tumor with BH, a pulsed focused US technique that produces non-thermal mechanical ablation of targeted tissues, or a sham US procedure. Treatments targeted approximately 50% of the largest RCC with a margin of normal kidney. BH treated rats were euthanized at 1 (n = 4) or 48 (n = 4) h, and sham patients (n = 4) at 48 h. Circulating plasma cytokine levels were assessed with multiplex assays before and at 0.25, 1, 4, 24 and 48 h following treatment. Kidneys were collected and processed for histologic assessment, immunohistochemistry and intrarenal cytokine concentration measurements. For statistical analysis Student's t-test was used. US-guided BH treatment was successful in all animals, producing hypoechoic regions within the targeted volume consistent with BH treatment effect. Grossly, regions of homogenized tissue were apparent with evidence of focal intra-parenchymal hemorrhage. Histologically, BH produced a sharply demarcated region of homogenized tumor and non-tumor tissue containing acellular debris. BH treatment was associated with significantly increased relative concentration of plasma TNF versus sham treatment (p < 0.05) and transient elevations in high-mobility group box 1 (HMGB1), IL-10 and IL-6 consistent with acute inflammatory response to trauma. Intrarenal cytokine concentrations followed the same trend. At 48 h, enhanced infiltration of CD8+ T cells was observed by immunohistochemistry in both the treated and un-treated contralateral RCC/kidneys in BH-treated animals versus sham treatment. BH treatment was well tolerated with transient gross hematuria and a perinephric hematoma developing in one subject each. The study demonstrates the feasibility of BH ablation of de novo RCC and suggests activation of the acute inflammatory cascade following treatment that appears to stimulate CD8+ T cell infiltration of both treated and untreated tumors. Longer duration chronic studies are ongoing to characterize the longevity and robustness of this response.

  View details for DOI 10.1016/j.ultrasmedbio.2018.09.006

  View details for PubMedID 30340920

• GIE Editorial Board top 10 topics: advances in GI endoscopy in 2018. Gastrointestinal endoscopy Cohen, J. n., Desilets, D. J., Hwang, J. H., Kyanam Kabir Baig, K. R., Leung, F. W., Maranki, J. L., Okolo, P. I., Swanstrom, L. L., Chak, A. n. 2019

  Abstract

  The ASGE's GIE Editorial Board reviewed original endoscopy-related articles published during 2018 in GIE and 10 other leading medical and gastroenterology journals. Votes from each individual member were tallied to identify a consensus list of 10 topic areas of major advances in gastrointestinal endoscopy. Individual board members summarized important findings published in these 10 areas of adenoma detection, bariatric endoscopy, endoscopic mucosal resection (EMR)/submucosal dissection (ESD)/full thickness resection (EFTR), artificial intelligence, expandable metal stents for palliation of biliary obstruction, pancreatic therapy with lumen apposing metal stents, endoscope reprocessing, Barrett's esophagus, interventional EUS, and gastrointestinal bleeding. This document summarizes these "Top 10" endoscopic advances of 2018.

  View details for DOI 10.1016/j.gie.2019.03.020

  View details for PubMedID 30928425

• Efficacy of a novel endoscopically deliverable muco-adhesive hemostatic powder in an acute gastric bleeding porcine model. PloS one Bang, B. n., Lee, E. n., Maeng, J. n., Kim, K. n., Hwang, J. H., Hyon, S. H., Hyon, W. n., Lee, D. H. 2019; 14 (6): e0216829

  Abstract

  This study investigated the effectiveness of new hemostatic adhesive powder (UI-EWD) in a swine mode of acute gastric bleeding. Gastric ulcer bleeding was induced endoscopically at two locations in each of eight heparinized mini-pigs. UI-EWD and saline were sprayed endoscopically in the experimental (n = 5) and control groups (n = 3), respectively. The hemostatic effect and hydrogel persistence on ulcers were periodically evaluated endoscopically. Initial hemostasis was achieved successfully in all lesions in the experimental group. Follow-up endoscopy showed minor delayed bleeding in 10% at 6 hours in the experimental group, whereas re-bleeding was observed in 50% at 6 hours in the control group. UI-EWD gel persisted at 90%, 80%, and 50% of ulcer bases at 6, 18, and 42 hours post-application, respectively. This study suggests that muco-adhesive UI-EWD may be effective in the endoscopic treatment of active ulcer bleeding.

  View details for DOI 10.1371/journal.pone.0216829

  View details for PubMedID 31185029

• Prevalence, Risk Factors, and Surveillance Patterns for Gastric Intestinal Metaplasia Among Patients Undergoing Upper Endoscopy with Biopsy. Gastrointestinal endoscopy Huang, R. J., Ende, A. R., Singla, A. n., Higa, J. T., Choi, A. Y., Lee, A. B., Whang, S. G., Gravelle, K. n., D'Andrea, S. n., Bang, S. J., Schmidt, R. A., Yeh, M. M., Hwang, J. H. 2019

  Abstract

  Gastric intestinal metaplasia (GIM) is an important precursor lesion to gastric cancer (GC), the second leading cause of cancer deaths worldwide. There exist few data regarding the prevalence of, risk factors for, and clinical practice patterns regarding gastric intestinal metaplasia (GIM) in the United States. Furthermore, there are currently no U.S. guidelines regarding screening/surveillance for GIM.All consecutive upper endoscopic procedures from 2 academic medical centers in Seattle between 1999 and 2014 are reviewed. Demographic, clinical, and endoscopic covariates are recorded at time of endoscopy. Procedures with gastric biopsy are matched to final histologic diagnoses, including presence of Helicobacter pylori. Cases of GIM and dysplasia are recorded and compared with non-GIM controls using univariate and multivariable regression. Surveillance patterns for cases of GIM are recorded.Data from 36,799 upper endoscopies, 17,710 gastric biopsies, 2,073 cases of GIM, 43 cases of dysplasia, and 78 cases of GC were captured. The point prevalence of GIM is 11.7% in patients who underwent gastric biopsy. Non-white race (P<0.001), increasing age (P<0.001), and presence of H pylori (P<0.001) associated with GIM. Once GIM is present, increasing age (P<0.001) and male gender (P<0.001) associate with progression, and presence of H pylori (P<0.001) inversely associates with progression to dysplasia/GC. Few cases of GIM/dysplasia/GC are made during procedures for GIM screening/surveillance. Only 16% of patients with a diagnosis of GIM received a recommendation for surveillance.There is a high prevalence of GIM among non-white and Hispanic Americans. Risk factors for development of GIM may be distinct from risk factors for progression to GC.

  View details for DOI 10.1016/j.gie.2019.07.038

  View details for PubMedID 31425693

• Low Frequency of Lymph Node Metastases in Patients in the United States With Early-stage Gastric Cancers That Fulfill Japanese Endoscopic Resection Criteria. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Hanada, Y., Choi, A. Y., Hwang, J. H., Draganov, P. V., Khanna, L., Sethi, A., Bartel, M. J., Goel, N., Abe, S., De Latour, R. A., Park, K., Melis, M., Newman, E., Hatzaras, I., Reddy, S. S., Farma, J. M., Liu, X., Schlachterman, A., Kresak, J., Trapp, G., Ansari, N., Schrope, B., Lee, J. Y., Dhall, D., Lo, S., Jamil, L. H., Burch, M., Gaddam, S., Gong, Y., Del Portillo, A., Tomizawa, Y., Truong, C. D., Brewer Gutierrez, O. I., Montgomery, E., Johnston, F. M., Duncan, M., Canto, M., Ahuja, N., Lennon, A. M., Ngamruengphong, S. 2018

  Abstract

  BACKGROUND & AIMS: In the West, early gastric cancer is increasingly managed with endoscopic resection (ER). This is, however, based on the assumption that the low prevalence and risk of lymph node metastases observed in Asian patients is applicable to patients in the United States. We sought to evaluate the frequency of and factors associated with metastasis of early gastric cancers to lymph nodes, and whether the Japanese ER criteria are applicable to patients in the US.METHODS: We performed a retrospective study of 176 patients (mean age 68.5 years; 59.1% male; 58.5% Caucasian) who underwent surgical resection with lymph node dissection of T1 and Tis gastric adenocarcinomas, staged by pathologists, at 7 tertiary care centers in the US from January 1, 1999 through December 31, 2016. The frequency of lymph node metastases and associated risk factors were determined.RESULTS: The mean size of gastric adenocarcinomas was 23.0±16.6 mm-most were located in the lower-third of the stomach (67.0%), invading the submucosa (55.1%), and moderately differentiated (31.3%). Lymphovascular invasion was observed in 18.2% of lesions. Overall, 20.5% of patients had lymph node metastases. Submucosal invasion (odds ratio, 3.9; 95% CI 1.4-10.7) and lymphovascular invasion (odds ratio, 4.6; 95% CI, 1.8-12.0) were independently associated with increased risk of metastasis to lymph nodes. The frequency of lymph node metastases among patients fulfilling standard and expanded Japanese criteria for ER were 0 and 7.5%, respectively.CONCLUSION: The frequency of lymph node metastases among patients with early gastric cancer in a US population is higher than that of published Asian series. However, early gastric cancer lesions that meet the Japanese standard criteria for ER are associated with negligible risk of metastasis to lymph nodes, so ER can be recommended for definitive therapy. Expanded criteria cancers appear to have a higher risk of metastasis to lymph nodes, so ER may be considered for select cases.

  View details for PubMedID 30471457

• ENDOSCOPIC SUBMUCOSAL DISSECTION (ESD) AS A SALVAGE THERAPY FOR PATIENTS WITH RECURRECE OR PROGRESSION OF BARRETT'S ESOPHAGUS (BE) RELATED EARLY NEOPLASIA AFTER STANDARD ENDOSCOPIC MANAGEMENT IS FEASIBLE AND SAFE : A US MULTI-CENTER STUDY Tomizawa, Y., Friedland, S., Hwang, J. MOSBY-ELSEVIER. 2018: AB281–AB282

  View details for Web of Science ID 000434248200494

• Understanding Gastric Cancer Risk Factors: We Need to Close the Gap GUT AND LIVER Hwang, J. 2018; 12 (1): 1–2

  View details for DOI 10.5009/gnl17503

  View details for Web of Science ID 000423401300001

  View details for PubMedID 29284218

  View details for PubMedCentralID PMC5753676

• Hyperthermia-enhanced targeted drug delivery using magnetic resonance-guided focussed ultrasound: a pre-clinical study in a genetic model of pancreatic cancer. International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group Farr, N. n., Wang, Y. N., D'Andrea, S. n., Starr, F. n., Partanen, A. n., Gravelle, K. M., McCune, J. S., Risler, L. J., Whang, S. G., Chang, A. n., Hingorani, S. R., Lee, D. n., Hwang, J. H. 2018; 34 (3): 284–91

  Abstract

  The lack of effective treatment options for pancreatic cancer has led to a 5-year survival rate of just 8%. Here, we evaluate the ability to enhance targeted drug delivery using mild hyperthermia in combination with the systemic administration of a low-temperature sensitive liposomal formulation of doxorubicin (LTSL-Dox) using a relevant model for pancreas cancer.Experiments were performed in a genetically engineered mouse model of pancreatic cancer (KPC mice: LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre). LTSL-Dox or free doxorubicin (Dox) was administered via a tail vein catheter. A clinical magnetic resonance-guided high intensity focussed ultrasound (MR-HIFU) system was used to plan treatment, apply the HIFU-induce hyperthermia and monitor therapy. Post-therapy, total Dox concentration in tumour tissue was determined by HPLC and confirmed with fluorescence microscopy.Localized hyperthermia was successfully applied and monitored with a clinical MR-HIFU system. The mild hyperthermia heating algorithm administered by the MR-HIFU system resulted in homogenous heating within the region of interest. MR-HIFU, in combination with LTSL-Dox, resulted in a 23-fold increase in the localised drug concentration and nuclear uptake of doxorubicin within the tumour tissue of KPC mice compared to LTSL-Dox alone. Hyperthermia, in combination with free Dox, resulted in a 2-fold increase compared to Dox alone.This study demonstrates that HIFU-induced hyperthermia in combination with LTSL-Dox can be a non-invasive and effective method in enhancing the localised delivery and penetration of doxorubicin into pancreatic tumours.

  View details for DOI 10.1080/02656736.2017.1336675

  View details for PubMedID 28715967

  View details for PubMedCentralID PMC6135238

• Guidelines for sedation and anesthesia in GI endoscopy. Gastrointestinal endoscopy Early, D. S., Lightdale, J. R., Vargo, J. J., Acosta, R. D., Chandrasekhara, V. n., Chathadi, K. V., Evans, J. A., Fisher, D. A., Fonkalsrud, L. n., Hwang, J. H., Khashab, M. A., Muthusamy, V. R., Pasha, S. F., Saltzman, J. R., Shergill, A. K., Cash, B. D., DeWitt, J. M. 2018; 87 (2): 327–37

  View details for DOI 10.1016/j.gie.2017.07.018

  View details for PubMedID 29306520

• Gastrointestinal Endoscopy Editorial Board top 10 topics: advances in GI endoscopy in 2017. Gastrointestinal endoscopy Desilets, D. J., Hwang, J. H., Kyanam Kabir Baig, K. R., Leung, F. W., Maranki, J. L., Mishra, G. n., Shah, R. J., Swanstrom, L. L., Chak, A. n. 2018; 88 (1): 1–8

  View details for DOI 10.1016/j.gie.2018.04.2333

  View details for PubMedID 29779609

• Evaluation of pancreatic tumor development in KPC mice using multi-parametric MRI. Cancer imaging : the official publication of the International Cancer Imaging Society Vohra, R. n., Park, J. n., Wang, Y. N., Gravelle, K. n., Whang, S. n., Hwang, J. H., Lee, D. n. 2018; 18 (1): 41

  Abstract

  Pancreatic ductal adenocarcinoma (PDA) is a fatal disease with very poor prognosis. Development of sensitive and noninvasive methods to monitor tumor progression in PDA is a critical and unmet need. Magnetic resonance imaging (MRI) can noninvasively provide information regarding underlying pathophysiological processes such as necrosis, inflammatory changes and fibrotic tissue deposition.A genetically engineered KPC mouse model that recapitulates human PDA was used to characterize disease progression. MR measures of T1 and T2 relaxation times, magnetization transfer ratio (MTR), diffusion and chemical exchange saturation transfer were compared in two separate phases i.e. slow and rapid growth phase of tumor. Fibrotic tissue accumulation was assessed histologically using Masson's trichrome staining. Pearson correlation coefficient (r) was computed to assess the relationship between the fibrotic tissue accumulation and different MR parameters.There was a negative correlation between amide proton transfer signal intensity and tumor volume (r = - 0.63, p = 0.003) in the slow growth phase of the tumor development. In the terminal stage of rapid growth phase of the tumor development MTR was strongly correlated with tumor volume (r = 0.62, p = 0.008). Finally, MTR was significantly correlated with % fibrosis (r = 0.87; p < 0.01), followed by moderate correlation between tumor volume (r = 0.42); T1 (r = - 0.61), T2 (r = - 0.61) and accumulation of fibrotic tissue.Here we demonstrated, using multi-parametric MRI (mp-MRI), that MRI parameters changed with tumor progression in a mouse model of PDA. Use of mp-MRI may have the potential to monitor the dynamic changes of tumor microenvironment with increase in tumor size in the transgenic KPC mouse model of pancreatic tumor.

  View details for DOI 10.1186/s40644-018-0172-6

  View details for PubMedID 30409175

  View details for PubMedCentralID PMC6225661

• Objective Differences in Colonoscopy Technique Between Trainee and Expert Endoscopists Using the Colonoscopy Force Monitor. Digestive diseases and sciences Ende, A. R., De Groen, P. n., Balmadrid, B. L., Hwang, J. H., Inadomi, J. n., Wojtera, T. n., Egorov, V. n., Sarvazyan, N. n., Korman, L. n. 2018; 63 (1): 46–52

  Abstract

  Learning to perform colonoscopy safely and effectively is central to gastroenterology fellowship programs. The application of force to the colonoscope is an important part of colonoscopy technique.We compared force application during colonoscopy between novice and expert endoscopists using a novel device to determine differences in colonoscopy technique.This is an observational cohort study designed to compare force application during colonoscopy between novice and experienced trainees, made up of gastroenterology fellows from two training programs, and expert endoscopists from both academic and private practice settings.Force recordings were obtained for 257 colonoscopies by 37 endoscopists, 21 of whom were trainees. Experts used higher average forward forces during insertion compared to all trainees and significantly less clockwise torque compared to novice trainees.We present significant, objective differences in colonoscopy technique between novice trainees, experienced trainees, and expert endoscopists. These findings suggest that the colonoscopy force monitor is an objective tool for measuring proficiency in colonoscopy. Furthermore, the device may be used as a teaching tool in training and continued medical education programs.

  View details for DOI 10.1007/s10620-017-4847-9

  View details for PubMedID 29147876

• A Chance to Cut Is a Chance to Cure: Endoscopic Submucosal Dissection for Early Gastric Cancer. Digestive diseases and sciences Huang, R. J., Charville, G. W., Hwang, J. H., Friedland, S. n. 2018

  View details for PubMedID 30350240

• Noninvasive characterization of pancreatic tumor mouse models using magnetic resonance imaging CANCER MEDICINE Farr, N., Wang, Y., D'Andrea, S., Gravelle, K. M., Hwang, J. H., Lee, D. 2017; 6 (5): 1082-1090

  Abstract

  The preclinical models of pancreatic adenocarcinoma provide an alternative means for determining the mechanisms of malignancy and possibilities for treatments, thus representing a resource of immense potential for cancer treatment in medicine. To evaluate different tumor models, quantifiable magnetic resonance imaging (MRI) techniques can play a significant role in identifying valuable in vivo biomarkers of tumor characteristics. We characterized three models of pancreatic cancer with multiparametric MRI techniques. Tumor stromal density of each tumor was measured using diffusion-weighted imaging and magnetization transfer (MT-MRI). Histologic measurement showed a similar trend with tumor fibrosis levels. Results indicated that MRI measurements can serve as a valuable tool in identifying and evaluating tumor characteristics.

  View details for DOI 10.1002/cam4.1062

  View details for Web of Science ID 000401330300020

  View details for PubMedID 28390098

  View details for PubMedCentralID PMC5430104

• Release of Cell-free MicroRNA Tumor Biomarkers into the Blood Circulation with Pulsed Focused Ultrasound: A Noninvasive, Anatomically Localized, Molecular Liquid Biopsy. Radiology Chevillet, J. R., Khokhlova, T. D., Giraldez, M. D., Schade, G. R., Starr, F., Wang, Y., Gallichotte, E. N., Wang, K., Hwang, J. H., Tewari, M. 2017; 283 (1): 158-167

  Abstract

  Purpose To compare the abilities of three pulsed focused ultrasound regimes (that cause tissue liquefaction, permeabilization, or mild heating) to release tumor-derived microRNA into the circulation in vivo and to evaluate release dynamics. Materials and Methods All rat experiments were approved by the University of Washington Institutional Animal Care and Use Committee. Reverse-transcription quantitative polymerase chain reaction array profiling was used to identify candidate microRNA biomarkers in a rat solid tumor cell line. Rats subcutaneously grafted with these cells were randomly assigned among three pulsed focused ultrasound treatment groups: (a) local tissue liquefaction via boiling histotripsy, (b) tissue permeabilization via inertial cavitation, and (c) mild (<10°C) heating of tissue, as well as a sham-treated control group. Blood specimens were drawn immediately prior to treatment and serially over 24 hours afterward. Plasma microRNA was quantified with reverse-transcription quantitative polymerase chain reaction, and statistical significance was determined with one-way analysis of variance (Kruskal-Wallis and Friedman tests), followed by the Dunn multiple-comparisons test. Results After tissue liquefaction and cavitation treatments (but not mild heating), plasma quantities of candidate biomarkers increased significantly (P value range, <.0001 to .04) relative to sham-treated controls. A threefold to 32-fold increase occurred within 15 minutes after initiation of pulsed focused ultrasound tumor treatment, and these increases persisted for 3 hours. Histologic examination confirmed complete liquefaction of the targeted tumor area with boiling histotripsy, in addition to areas of petechial hemorrhage and tissue disruption by means of cavitation-based treatment. Conclusion Mechanical tumor tissue disruption with pulsed focused ultrasound-induced bubble activity significantly increases the plasma abundance of tumor-derived microRNA rapidly after treatment.©RSNA, 2016 Online supplemental material is available for this article.

  View details for DOI 10.1148/radiol.2016160024

  View details for PubMedID 27802108

  View details for PubMedCentralID PMC5375625

• Optimal strategies for pancreatic cyst surveillance: we need better comparative data, not more case series GASTROINTESTINAL ENDOSCOPY Vege, S., Ziring, B., Jain, R., Scheiman, J. M., Hwang, J., Moayyedi, P. 2017; 85 (3): 685-686

  View details for DOI 10.1016/j.gie.2016.09.007

  View details for Web of Science ID 000397169600039

  View details for PubMedID 28215775

• A meta-analysis of palliative treatment of pancreatic cancer with high intensity focused ultrasound. Journal of therapeutic ultrasound Dababou, S., Marrocchio, C., Rosenberg, J., Bitton, R., Pauly, K. B., Napoli, A., Hwang, J. H., Ghanouni, P. 2017; 5: 9-?

  Abstract

  Pancreatic adenocarcinoma is currently the fourth-leading cause of cancer-related death. Up to 60-90% of patients with advanced disease suffer cancer-related pain, severely impacting their quality of life. Current management involves primarily pharmacotherapy with opioid narcotics and celiac plexus neurolysis; unfortunately, both approaches offer transient relief and cause undesired side-effects. High intensity focused ultrasound (HIFU) is a non-invasive thermal ablation technique that has been used to treat pancreatic cancer. This meta-analysis aims to evaluate the role of HIFU in pain palliation of advanced unresectable pancreatic adenocarcinoma.An electronic search was performed in PubMed Medline database up to the end of July 2016, for unresectable pancreatic cancer pain palliation with HIFU. Pertinent studies were identified through the PubMed search engine using the following keywords: HIFU, pancreas, pancreatic cancer, pain and palliation. Additional studies were included after manual search of the selected bibliographies. Pain palliation results reported in each study were analyzed using a logit-transformed random-effects model using the inverse variance method, with the DerSimonian-Laird estimator for τ(2), and Cochran's Q test for heterogeneity among studies. The I(2) was calculated to assess the percentage of the total variability in the different effect size estimates that can be attributed to heterogeneity among the true effects. A rank correlation test of funnel plot asymmetry was done to assess possible publication bias.The meta-analysis includes a total number of 23 studies with 865 patients, 729 with pancreatic cancer. The population enrolled ranges from 3 patients in the smallest series, up to 61 in the largest study. τ(2) (variance among studies) was 0.195, and I(2) (percentage of variation among studies) was 40% (95% CI: 1-64%); the Q test p-value was 0.026, indicating significant heterogeneity among studies. Among 639 patients treated with HIFU, 567 complained of pancreatic pain before the treatment and 459 patients experienced partial or complete pain relief after treatment. The random effects estimate of the proportion of patients with pain reduction was 0.81 (95% CI: 0.76-86).HIFU appears to be an effective tool for pain palliation in advanced pancreatic cancer. Studies assessing treatment in patients with pancreatic adenocarcinoma are limited by factors such as small sample sizes and heterogeneity in clinical definitions and assessments. Prospective randomized and standardized studies are necessary to confirm the effectiveness of HIFU in relieving pain, and to evaluate for any potential impact on tumor control and patient survival.

  View details for DOI 10.1186/s40349-017-0080-4

  View details for PubMedID 28373906

• Focused ultrasound for immuno-adjuvant treatment of pancreatic cancer: An emerging clinical paradigm in the era of personalized oncotherapy. International reviews of immunology Maloney, E. n., Khokhlova, T. n., Pillarisetty, V. G., Schade, G. R., Repasky, E. A., Wang, Y. N., Giuliani, L. n., Primavera, M. n., Hwang, J. H. 2017; 36 (6): 338–51

  Abstract

  Current clinical treatment regimens, including many emergent immune strategies (e.g., checkpoint inhibitors) have done little to affect the devastating course of pancreatic ductal adenocarcinoma (PDA). Clinical trials for PDA often employ multi-modal treatment, and have started to incorporate stromal-targeted therapies, which have shown promising results in early reports. Focused ultrasound (FUS) is one such therapy that is uniquely equipped to address local and systemic limitations of conventional cancer therapies as well as emergent immune therapies for PDA. FUS methods can non-invasively generate mechanical and/or thermal effects that capitalize on the unique oncogenomic/proteomic signature of a tumor. Potential benefits of FUS therapy for PDA include: (1) emulsification of targeted tumor into undenatured antigens in situ, increasing dendritic cell maturation, and increasing intra-tumoral CD8+/ T regulatory cell ratio and CD8+T cell activity; (2) reduction in intra-tumoral hypoxic stress; (3) modulation of tumor cell membrane protein localization to enhance immunogenicity; (4) modulation of the local cytokine milieu toward a Th1-type inflammatory profile; (5) up-regulation of local chemoattractants; (6) remodeling the tumor stroma; (7) localized delivery of exogenously packaged immune-stimulating antigens, genes and therapeutic drugs. While not all of these results have been studied in experimental PDA models to date, the principles garnered from other solid tumor and disease models have direct relevance to the design of optimal FUS protocols for PDA. In this review, we address the pertinent limitations in current and emergent immune therapies that can be improved with FUS therapy for PDA.

  View details for DOI 10.1080/08830185.2017.1363199

  View details for PubMedID 28961038

• EUS and related technologies for the diagnosis and treatment of pancreatic disease: research gaps and opportunities-Summary of a National Institute of Diabetes and Digestive and Kidney Diseases workshop. Gastrointestinal endoscopy Lee, L. S., Andersen, D. K., Ashida, R. n., Brugge, W. R., Canto, M. I., Chang, K. J., Chari, S. T., DeWitt, J. n., Hwang, J. H., Khashab, M. A., Kim, K. n., Levy, M. J., McGrath, K. n., Park, W. G., Singhi, A. n., Stevens, T. n., Thompson, C. C., Topazian, M. D., Wallace, M. B., Wani, S. n., Waxman, I. n., Yadav, D. n., Singh, V. K. 2017; 86 (5): 768–78

  Abstract

  A workshop was sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases to address the research gaps and opportunities in pancreatic EUS. The event occurred on July 26, 2017 in 4 sessions: (1) benign pancreatic diseases, (2) high-risk pancreatic diseases, (3) diagnostic and therapeutics, and (4) new technologies. The current state of knowledge was reviewed, with identification of numerous gaps in knowledge and research needs. Common themes included the need for large multicenter consortia of various pancreatic diseases to facilitate meaningful research of these entities; to standardize EUS features of different pancreatic disorders, the technique of sampling pancreatic lesions, and the performance of various therapeutic EUS procedures; and to identify high-risk disease early at the cellular level before macroscopic disease develops. The need for specialized tools and accessories to enable the safe and effective performance of therapeutic EUS procedures also was discussed.

  View details for PubMedID 28941651

• The impact of medical tourism on colorectal screening among Korean Americans: A community-based cross-sectional study BMC CANCER Ko, L. K., Taylor, V. M., Yoon, J., Copeland, W. K., Hwang, J. H., Lee, E. J., Inadomi, J. 2016; 16

  Abstract

  Colorectal cancer (CRC) remains the most commonly diagnosed cancer among Korean Americans (KAs) in part due to low screening rates. Recent studies suggest that some KA patients engage in medical tourism and receive medical care in their home country. The impact of medical tourism on CRC screening is unknown. The purpose of this paper was to 1) investigate the frequency of medical tourism, 2) examine the association between medical tourism and CRC screening, and 3) characterize KA patients who engage in medical tourism.This is a community-based, cross-sectional study involving self-administered questionnaires conducted from August 2013 to October 2013. Data was collected on 193 KA patients, ages 50-75, residing in the Seattle metropolitan area. The outcome variable is up-to-date with CRC screening, defined as having had a stool test (Fecal Occult Blood Test or Fecal Immunochemical Test) within the past year or a colonoscopy within 10 years. Predictor variables are socio-demographics, health factors, acculturation, knowledge, financial concerns for medical care costs, and medical tourism.In multi-variate modeling, medical tourism was significantly related to being up-to-date with CRC screening. Participants who engaged in medical tourism had 8.91 (95% CI: 3.89-23.89) greater odds of being up-to-date with CRC screening compared to those who did not travel for healthcare. Factors associated with engaging in medical tourism were lack of insurance coverage (P = 0.008), higher levels of education (P = 0.003), not having a usual place of care (P = 0.002), older age at immigration (P = 0.009), shorter years-of-stay in the US (P = 0.003), and being less likely to speak English well (P = 0.03).This study identifies the impact of medical tourism on CRC screening and characteristics of KA patients who report engaging in medical tourism. Healthcare providers in the US should be aware of the customary nature of medical tourism among KAs and consider assessing medical tests done abroad when providing cancer care.Not applicable.

  View details for DOI 10.1186/s12885-016-2965-y

  View details for Web of Science ID 000389382000005

  View details for PubMedID 27905896

  View details for PubMedCentralID PMC5134124

• Gastric intestinal metaplasia: An irreversible risk factor for gastric cancer? GASTROINTESTINAL ENDOSCOPY Higa, J. T., Hwang, J. 2016; 84 (4): 625-627

  View details for DOI 10.1016/j.gie.2016.04.028

  View details for Web of Science ID 000389543000009

  View details for PubMedID 27633357

• Devices and techniques for ERCP in the surgically altered GI tract GASTROINTESTINAL ENDOSCOPY Enestvedt, B. K., Kothari, S., Pannala, R., Yang, J., Fujii-Lau, L. L., Hwang, J. H., Konda, V., Manfredi, M., Maple, J. T., Murad, F. M., Woods, K. L., Banerjee, S. 2016; 83 (6): 1061-1075

  View details for DOI 10.1016/j.gie.2016.03.018

  View details for Web of Science ID 000376181700002

  View details for PubMedID 27103361

• The use of carbon dioxide in gastrointestinal endoscopy GASTROINTESTINAL ENDOSCOPY Lo, S. K., Fujii-Lau, L. L., Enestvedt, B. K., Hwang, J. H., Konda, V., Manfredi, M. A., Maple, J. T., Murad, F. M., Pannala, R., Woods, K. L., Banerjee, S. 2016; 83 (5): 857-865

  View details for DOI 10.1016/j.gie.2016.01.046

  View details for Web of Science ID 000374441300001

  View details for PubMedID 26946413

• ENHANCEMENT OF SMALL MOLECULE DELIVERY BY PULSED HIGH-INTENSITY FOCUSED ULTRASOUND: A PARAMETER EXPLORATION ULTRASOUND IN MEDICINE AND BIOLOGY Zhou, Y., Wang, Y., Farr, N., Zia, J., Chen, H., Ko, B. M., Khokhlova, T., Li, T., Hwang, J. H. 2016; 42 (4): 956-963

  Abstract

  Chemotherapeutic drug delivery is often ineffective within solid tumors, but increasing the drug dose would result in systemic toxicity. The use of high-intensity focused ultrasound (HIFU) has the potential to enhance penetration of small molecules. However, operation parameters need to be optimized before the use of chemotherapeutic drugs in vivo and translation to clinical trials. In this study, the effects of pulsed HIFU (pHIFU) parameters (spatial-average pulse-average intensity, duty factor and pulse repetition frequency) on the penetration as well as content of small molecules were evaluated in ex vivo porcine kidneys. Specific HIFU parameters resulted in more than 40 times greater Evans blue content and 3.5 times the penetration depth compared with untreated samples. When selected parameters were applied to porcine kidneys in vivo, a 2.3-fold increase in concentration was obtained after a 2-min exposure to pHIFU. Pulsed HIFU has been found to be an effective modality to enhance both the concentration and penetration depth of small molecules in tissue using the optimized HIFU parameters. Although, performed in normal tissue, this study has the promise of translation into tumor tissue.

  View details for DOI 10.1016/j.ultrasmedbio.2015.12.009

  View details for Web of Science ID 000373384700014

  View details for PubMedID 26803389

  View details for PubMedCentralID PMC4775378

• The role of endoscopy in the evaluation and management of patients with solid pancreatic neoplasia GASTROINTESTINAL ENDOSCOPY Eloubeidi, M. A., Decker, G. A., Chandrasekhara, V., Chathadi, K. V., Early, D. S., Evans, J. A., Fanelli, R. D., Fisher, D. A., Foley, K., Hwang, J. H., Jue, T. L., Lightdale, J. R., Pasha, S. F., Saltzman, J. R., Sharaf, R., Shergill, A. K., Cash, B. D., Dewitt, J. M. 2016; 83 (1): 17-28

  View details for DOI 10.1016/j.gie.2015.09.009

  View details for Web of Science ID 000369230900004

  View details for PubMedID 26706297

• HIFU for Palliative Treatment of Pancreatic Cancer THERAPEUTIC ULTRASOUND Khokhlova, T. D., Hwang, J. H. 2016; 880: 83-95

  Abstract

  Pancreatic cancer is one of the deadliest malignancies, with only a 6 % 5-year survival rate and over 50 % of patients being diagnosed at the advanced stage. Current therapies are ineffective, and the treatment of patients with advanced disease is palliative. In the past decade, HIFU ablation has emerged as a modality for palliative treatment of pancreatic tumors. Multiple preclinical and non-randomized clinical trials have been performed to evaluate the safety and efficacy of this procedure. Substantial tumor-related pain reduction was achieved in most cases after HIFU treatment and few significant side effects were observed. In addition, some studies indicate that combination of HIFU ablation with chemotherapy may provide a survival benefit. This chapter summarizes the pre-clinical and clinical experience obtained to date in HIFU treatment of pancreatic tumors and discusses the challenges, limitations and new approaches in this modality.

  View details for DOI 10.1007/978-3-319-22536-4_5

  View details for Web of Science ID 000369481100006

  View details for PubMedID 26486333

• The management of antithrombotic agents for patients undergoing GI endoscopy GASTROINTESTINAL ENDOSCOPY Acosta, R. D., Abraham, N. S., Chandrasekhara, V., Chathadi, K. V., Early, D. S., Eloubeidi, M. A., Evans, J. A., Faulx, A. L., Fisher, D. A., Fonkalsrud, L., Hwang, J. H., Khashab, M. A., Lightdale, J. R., Muthusamy, V. R., Pasha, S. F., Saltzman, J. R., Shaukat, A., Shergill, A. K., Wang, A., Cash, B. D., Dewitt, J. M. 2016; 83 (1): 3-16

  View details for DOI 10.1016/j.gie.2015.09.035

  View details for Web of Science ID 000369230900003

  View details for PubMedID 26621548

• Endoscopic electronic medical record systems GASTROINTESTINAL ENDOSCOPY Manfredi, M. A., Manfredi, M. A., Chauhan, S. S., Enestvedt, B. K., Fujii-Lau, L. L., Konda, V., Hwang, J. H., Lo, S. K., Maple, J. T., Murad, F. M., Pannala, R., Woods, K. L., Banerjee, S. 2016; 83 (1): 29-36

  View details for DOI 10.1016/j.gie.2015.09.036

  View details for Web of Science ID 000369230900005

  View details for PubMedID 26616725

• Endoscopic resection of gastric and esophageal cancer. Gastroenterology report Balmadrid, B., Hwang, J. H. 2015; 3 (4): 330-338

  Abstract

  Endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) techniques have reduced the need for surgery in early esophageal and gastric cancers and thus has lessened morbidity and mortality in these diseases. ESD is a relatively new technique in western countries and requires rigorous training to reproduce the proficiency of Asian countries, such as Korea and Japan, which have very high complete (en bloc) resection rates and low complication rates. EMR plays a valuable role in early esophageal cancers. ESD has shown better en bloc resection rates but it is easier to master and maintain proficiency in EMR; it also requires less procedural time. For early esophageal adenocarcinoma arising from Barrett's, ESD and EMR techniques are usually combined with other ablative modalities, the most common being radiofrequency ablation because it has the largest dataset to prove its success. The EMR techniques have been used with some success in early gastric cancers but ESD is currently preferred for most of these lesions. ESD has the added advantage of resecting into the submucosa and thus allowing for endoscopic resection of more aggressive (deeper) early gastric cancer.

  View details for DOI 10.1093/gastro/gov050

  View details for PubMedID 26510452

  View details for PubMedCentralID PMC4650978

• Therapeutic potential of ultrasound microbubbles in gastrointestinal oncology: recent advances and future prospects THERAPEUTIC ADVANCES IN GASTROENTEROLOGY Khokhlova, T. D., Haider, Y., Hwang, J. H. 2015; 8 (6): 384-394

  Abstract

  Microbubbles were initially invented as contrast agents for ultrasound imaging. However, lately more and more therapeutic applications of microbubbles are emerging, mostly related to drug and gene delivery. Ultrasound is a safe and noninvasive therapeutic modality which has the unique ability to interact with microbubbles and release their payload in situ in addition to permeabilizing the target tissues. The combination of drug-loaded microbubbles and ultrasound has been used in preclinical studies on blood-brain barrier opening, drug and gene delivery to solid tumors, and ablation of blood vessels. This review covers the basic principles of ultrasound-microbubble interaction, the types of microbubbles and the effect they have on tissue, and the preclinical and clinical experience with this approach to date in the field of gastrointestinal oncology.

  View details for DOI 10.1177/1756283X15592584

  View details for Web of Science ID 000363413400007

  View details for PubMedID 26557894

  View details for PubMedCentralID PMC4622285

• Is screening and surveillance for early detection of gastric cancer needed in Korean Americans? KOREAN JOURNAL OF INTERNAL MEDICINE Kim, G. H., Bang, S. J., Ende, A. R., Hwang, J. H. 2015; 30 (6): 747-758

  Abstract

  The incidence rate of gastric cancer in Korean Americans is over five times higher than that in non-Hispanic whites, and is similar to the incidence of colorectal cancer in the overall United States population. In Korea, the National Cancer Screening Program recommends endoscopy or upper gastrointestinal series for people aged 40 years and older every 2 years. However, the benefit of gastric cancer screening in Korean Americans has not been evaluated. Based on epidemiologic studies, Korean Americans appear to have more similar gastric cancer risk factors to Koreans as opposed to Americans of European descent, though the risk of gastric cancer appears to decrease for subsequent generations. Therefore, in accordance with recent recommendations regarding screening for gastric cancer in Korea, endoscopic screening for gastric cancer in Korean Americans should be considered, especially in those with known atrophic gastritis/intestinal metaplasia or a family history of gastric cancer. In the future, additional studies will needed to assess whether a screening program for gastric cancer in Korean Americans will result in a survival benefit.

  View details for DOI 10.3904/kjim.2015.30.6.747

  View details for Web of Science ID 000366667300001

  View details for PubMedID 26552450

  View details for PubMedCentralID PMC4642004

• Pulsed High-Intensity Focused Ultrasound Enhances Delivery of Doxorubicin in a Preclinical Model of Pancreatic Cancer CANCER RESEARCH Li, T., Wang, Y., Khokhlova, T. D., D'Andrea, S., Starr, F., Chen, H., McCune, J. S., Risler, L. J., Mashadi-Hossein, A., Hwang, J. H. 2015; 75 (18): 3738-3746

  Abstract

  Pancreatic cancer is characterized by extensive stromal desmoplasia, which decreases blood perfusion and impedes chemotherapy delivery. Breaking the stromal barrier could both increase perfusion and permeabilize the tumor, enhancing chemotherapy penetration. Mechanical disruption of the stroma can be achieved using ultrasound-induced bubble activity-cavitation. Cavitation is also known to result in microstreaming and could have the added benefit of actively enhancing diffusion into the tumors. Here, we report the ability to enhance chemotherapeutic drug doxorubicin penetration using ultrasound-induced cavitation in a genetically engineered mouse model (KPC mouse) of pancreatic ductal adenocarcinoma. To induce localized inertial cavitation in pancreatic tumors, pulsed high-intensity focused ultrasound (pHIFU) was used either during or before doxorubicin administration to elucidate the mechanisms of enhanced drug delivery (active vs. passive drug diffusion). For both types, the pHIFU exposures that were associated with high cavitation activity resulted in disruption of the highly fibrotic stromal matrix and enhanced the normalized doxorubicin concentration by up to 4.5-fold compared with controls. Furthermore, normalized doxorubicin concentration was associated with the cavitation metrics (P < 0.01), indicating that high and sustained cavitation results in increased chemotherapy penetration. No significant difference between the outcomes of the two types, that is, doxorubicin infusion during or after pHIFU treatment, was observed, suggesting that passive diffusion into previously permeabilized tissue is the major mechanism for the increase in drug concentration. Together, the data indicate that pHIFU treatment of pancreatic tumors when resulting in high and sustained cavitation can efficiently enhance chemotherapy delivery to pancreatic tumors. .

  View details for DOI 10.1158/0008-5472.CAN-15-0296

  View details for Web of Science ID 000363335800010

  View details for PubMedID 26216548

  View details for PubMedCentralID PMC4629806

• Endoscopic mucosal resection GASTROINTESTINAL ENDOSCOPY Hwang, J. H., Konda, V., Abu Dayyeh, B. K., Chauhan, S. S., Enestvedt, B. K., Fujii-Lau, L. L., Komanduri, S., Maple, J. T., Murad, F. M., Pannala, R., Thosani, N. C., Banerjee, S. 2015; 82 (2): 215-226

  Abstract

  EMR has become an established therapeutic option for premalignant and early-stage GI malignancies, particularly in the esophagus and colon. EMR can also aid in the diagnosis and therapy of subepithelial lesions localized to the muscularis mucosa or submucosa. Several dedicated EMR devices are available to facilitate these procedures. Adverse event rates, particularly bleeding and perforation, are higher after EMR relative to other basic endoscopic interventions but lower than adverse event rates for ESD. Endoscopists performing EMR should be knowledgeable and skilled in managing potential adverse events resulting from EMR.

  View details for DOI 10.1016/j.gie.2015.05.001

  View details for Web of Science ID 000357898100003

  View details for PubMedID 26077453

• The role of endoscopy in benign pancreatic disease GASTROINTESTINAL ENDOSCOPY Chandrasekhara, V., Chathadi, K. V., Acosta, R. D., Decker, G. A., Early, D. S., Eloubeidi, M. A., Evans, J. A., Faulx, A. L., Fanelli, R. D., Fisher, D. A., Foley, K., Fonkalsrud, L., Hwang, J. H., Jue, T. L., Khashab, M. A., Lightdale, J. R., Muthusamy, V. R., Pasha, S. F., Saltzman, J. R., Sharaf, R., Shaukat, A., Shergill, A. K., Wang, A., Cash, B. D., Dewitt, J. M. 2015; 82 (2): 203-214

  View details for DOI 10.1016/j.gie.2015.04.022

  View details for Web of Science ID 000357898100002

  View details for PubMedID 26077456

• The role of endoscopy in the management of premalignant and malignant conditions of the stomach GASTROINTESTINAL ENDOSCOPY Evans, J. A., Chandrasekhara, V., Chathadi, K. V., Decker, G. A., Early, D. S., Fisher, D. A., Foley, K., Hwang, J. H., Jue, T. L., Lightdale, J. R., Pasha, S. F., Sharaf, R., Shergill, A. K., Cash, B. D., Dewitt, J. M. 2015; 82 (1): 1-8

  View details for DOI 10.1016/j.gie.2015.03.1967

  View details for Web of Science ID 000356182600001

  View details for PubMedID 25935705

• Endoscopic submucosal dissection GASTROINTESTINAL ENDOSCOPY Maple, J. T., Abu Dayyeh, B. K., Chauhan, S. S., Hwang, J. H., Komanduri, S., Manfredi, M., Konda, V., Murad, F. M., Siddiqui, U. D., Banerjee, S. 2015; 81 (6): 1311-1325

  Abstract

  ESD is an established effective treatment modality for premalignant and early-stage malignant lesions of the stomach, esophagus, and colorectum. Compared with EMR, ESD is generally associated with higher rates of en bloc, R0, and curative resections and a lower rate of local recurrence. Oncologic outcomes with ESD compare favorably with competing surgical interventions, and ESD also serves as an excellent T-staging tool to identify noncurative resections that will require further treatment. ESD is technically demanding and has a higher rate of adverse events than most endoscopic procedures including EMR. As such,sufficient training is critical to ensure safe conduct and high-quality resections. A standardized training model for Western endoscopists has not been clearly established,but will be self-directed and include courses, animal model training, and optimally an observership at an expert center.Numerous dedicated ESD devices are now available in the United States from different manufacturers. Although the use of ESD in the United States is increasing, issues related to technical difficulty, limited training opportunities and mentors, risk of adverse events, long procedure duration,and suboptimal reimbursement may limit ESD adoption in the United States to a modest number of academic referral centers for the foreseeable future.

  View details for DOI 10.1016/j.gie.2014.12.010

  View details for Web of Science ID 000354558800002

  View details for PubMedID 25796422

• Learning models for endoscopic ultrasonography in gastrointestinal endoscopy WORLD JOURNAL OF GASTROENTEROLOGY Kim, G. H., Bang, S. J., Hwang, J. H. 2015; 21 (17): 5176-5182

  Abstract

  Endoscopic ultrasonography (EUS) has become a useful diagnostic and therapeutic modality in gastrointestinal endoscopy. However, EUS requires additional training since it requires simultaneous endoscopic manipulation and ultrasonographic interpretation. Obtaining adequate EUS training can be challenging since EUS is highly operator-dependent and training on actual patients can be associated with an increased risk of complications including inaccurate diagnosis. Therefore, several models have been developed to help facilitate training of EUS. The models currently available for EUS training include computer-based simulators, phantoms, ex vivo models, and live animal models. Although each model has its own merits and limitations, the value of these different models is rather complementary than competitive. However, there is a lack of objective data regarding the efficacy of each model with recommendations on the use of various training models based on expert opinion only. Therefore, objective studies evaluating the efficacy of various EUS training models on technical and clinical outcomes are still needed.

  View details for DOI 10.3748/wjg.v21.i17.5176

  View details for Web of Science ID 000353774100008

  View details for PubMedID 25954091

  View details for PubMedCentralID PMC4419058

• The role of endoscopy in inflammatory bowel disease GASTROINTESTINAL ENDOSCOPY Shergill, A. K., Lightdale, J. R., Bruining, D. H., Acosta, R. D., Chandrasekhara, V., Chathadi, K. V., Decker, G. A., Early, D. S., Evans, J. A., Fanelli, R. D., Fisher, D. A., Fonkalsrud, L., Foley, K., Hwang, J. H., Jue, T. L., Khashab, M. A., Muthusamy, V. R., Pasha, S. F., Saltzman, J. R., Sharaf, R., Cash, B. D., Dewitt, J. M. 2015; 81 (5): 1101-U389

  View details for DOI 10.1016/j.gie.2014.10.030

  View details for Web of Science ID 000352706600004

  View details for PubMedID 25800660

• Endoscopes and devices to improve colon polyp detection GASTROINTESTINAL ENDOSCOPY Konda, V., Chauhan, S. S., Abu Dayyeh, B. K., Hwang, J. H., Komanduri, S., Manfredi, M. A., Maple, J. T., Murad, F. M., Siddiqui, U. D., Banerjee, S. 2015; 81 (5): 1122-1129

  View details for DOI 10.1016/j.gie.2014.10.006

  View details for Web of Science ID 000352706600005

  View details for PubMedID 25746978

• Endoscopic high-intensity focused US: technical aspects and studies in an in vivo porcine model (with video) GASTROINTESTINAL ENDOSCOPY Li, T., Khokhlova, T., Maloney, E., Wang, Y., D'Andrea, S., Starr, F., Farr, N., Morrison, K., Keilman, G., Hwang, J. H. 2015; 81 (5): 1243-1250

  Abstract

  High-intensity focused US (HIFU) is becoming more widely used for noninvasive and minimally invasive ablation of benign and malignant tumors. Recent studies suggest that HIFU can also enhance targeted drug delivery and stimulate an antitumor immune response in many tumors. However, targeting pancreatic and liver tumors by using an extracorporeal source is challenging due to the lack of an adequate acoustic window. The development of an EUS-guided HIFU transducer has many potential benefits including improved targeting, decreased energy requirements, and decreased potential for injury to intervening structures.To design, develop, and test an EUS-guided HIFU transducer for endoscopic applications.A preclinical, pilot characterization and feasibility study.Academic research center.Studies were performed in an in vivo porcine model.Thermal ablation of in vivo porcine pancreas and liver was performed with EUS-guided focused US through the gastric tract.The transducer successfully created lesions in gel phantoms and ex vivo bovine livers. In vivo studies demonstrated that targeting and creating lesions in the porcine pancreas and liver are feasible.This was a preclinical, single-center feasibility study with a limited number of subjects.An EUS-guided HIFU transducer was successfully designed and developed with dimensions that are appropriate for endoscopic use. The feasibility of performing EUS-guided HIFU ablation in vivo was demonstrated in an in vivo porcine model. Further development of this technology will allow endoscopists to perform precise therapeutic ablation of periluminal lesions without breaching the wall of the gastric tract.

  View details for DOI 10.1016/j.gie.2014.12.019

  View details for Web of Science ID 000352706600023

  View details for PubMedID 25759124

  View details for PubMedCentralID PMC4452137

• Emerging HIFU applications in cancer therapy INTERNATIONAL JOURNAL OF HYPERTHERMIA Maloney, E., Hwang, J. H. 2015; 31 (3): 302-309

  Abstract

  High intensity focused ultrasound (HIFU), is a promising, non-invasive modality for treatment of tumours in conjunction with magnetic resonance imaging or diagnostic ultrasound guidance. HIFU is being used increasingly for treatment of prostate cancer and uterine fibroids. Over the last 10 years a growing number of clinical trials have examined HIFU treatment of both benign and malignant tumours of the liver, breast, pancreas, bone, connective tissue, thyroid, parathyroid, kidney and brain. For some of these emerging indications, HIFU is poised to become a serious alternative or adjunct to current standard treatments--including surgery, radiation, gene therapy, immunotherapy, and chemotherapy. Current commercially available HIFU devices are marketed for their thermal ablation applications. In the future, lower energy treatments may play a significant role in mediating targeted drug and gene delivery for cancer treatment. In this article we introduce currently available HIFU systems, provide an overview of clinical trials in emerging oncological targets, and briefly discuss selected pre-clinical research that is relevant to future oncological HIFU applications.

  View details for DOI 10.3109/02656736.2014.969789

  View details for Web of Science ID 000355926300011

  View details for PubMedID 25367011

• American Gastroenterological Association Technical Review on the Diagnosis and Management of Asymptomatic Neoplastic Pancreatic Cysts GASTROENTEROLOGY Scheiman, J. M., Hwang, J. H., Moayyedi, P. 2015; 148 (4): 824-U283

  View details for DOI 10.1053/j.gastro.2015.01.014

  View details for Web of Science ID 000351639000029

  View details for PubMedID 25805376

• Bowel preparation before colonoscopy GASTROINTESTINAL ENDOSCOPY Saltzman, J. R., Cash, B. D., Pasha, S. F., Early, D. S., Muthusamy, V. R., Khashab, M. A., Chathadi, K. V., Fanelli, R. D., Chandrasekhara, V., Lightdale, J. R., Fonkalsrud, L., Shergill, A. K., Hwang, J. H., Decker, G. A., Jue, T. L., Sharaf, R., Fisher, D. A., Evans, J. A., Foley, K., Shaukat, A., Eloubeidi, M. A., Faulx, A. L., Wang, A., Acosta, R. D. 2015; 81 (4): 781-794

  View details for DOI 10.1016/j.gie.2014.09.048

  View details for Web of Science ID 000351668700001

  View details for PubMedID 25595062

• The role of ERCP in benign diseases of the biliary tract GASTROINTESTINAL ENDOSCOPY Chathadi, K. V., Chandrasekhara, V., Acosta, R. D., Decker, G. A., Early, D. S., Eloubeidi, M. A., Evans, J. A., Faulx, A. L., Fanelli, R. D., Fisher, D. A., Foley, K., Fonkalsrud, L., Hwang, J. H., Jue, T. L., Khashab, M. A., Lightdale, J. R., Muthusamy, V. R., Pasha, S. F., Saltzman, J. R., Sharaf, R., Shaukat, A., Shergill, A. K., Wang, A., Cash, B. D., Dewitt, J. M. 2015; 81 (4): 795-803

  View details for DOI 10.1016/j.gie.2014.11.019

  View details for Web of Science ID 000351668700002

  View details for PubMedID 25665931

• ASGE Technology Committee systematic review and meta-analysis assessing the ASGE PIVI thresholds for adopting real-time endoscopic assessment of the histology of diminutive colorectal polyps. Gastrointestinal endoscopy Abu Dayyeh, B. K., Thosani, N., Konda, V., Wallace, M. B., Rex, D. K., Chauhan, S. S., Hwang, J. H., Komanduri, S., Manfredi, M., Maple, J. T., Murad, F. M., Siddiqui, U. D., Banerjee, S. 2015; 81 (3): 502 e1-502 e16

  Abstract

  In vivo real-time assessment of the histology of diminutive (≤5 mm) colorectal polyps detected at colonoscopy can be achieved by means of an "optical biopsy" by using currently available endoscopic technologies. This systematic review and meta-analysis was performed by the American Society for Gastrointestinal Endoscopy (ASGE) Technology Committee to specifically assess whether acceptable performance thresholds outlined by an ASGE Preservation and Incorporation of Valuable endoscopic Innovations (PIVI) document for clinical adoption of these technologies have been met. We conducted direct meta-analyses calculating the pooled negative predictive value (NPV) for narrow-band imaging (NBI), i-SCAN, and Fujinon Intelligent Color Enhancement (FICE)-assisted optical biopsy for predicting adenomatous polyp histology of small/diminutive colorectal polyps. We also calculated the pooled percentage agreement with histopathology when assigning postpolypectomy surveillance intervals based on combining real-time optical biopsy of colorectal polyps 5 mm or smaller with histopathologic assessment of polyps larger than 5 mm. Random-effects meta-analysis models were used. Statistical heterogeneity was evaluated by means of I(2) statistics. Our meta-analyses indicate that optical biopsy with NBI, exceeds the NPV threshold for adenomatous polyp histology, supporting a "diagnose-and-leave" strategy for diminutive predicted nonneoplastic polyps in the rectosigmoid colon. The pooled NPV of NBI for adenomatous polyp histology by using the random-effects model was 91% (95% confidence interval [CI], 88-94). This finding was associated with a high degree of heterogeneity (I(2) = 89%). Subgroup analysis indicated that the pooled NPV was greater than 90% for academic medical centers (91.8%; 95% CI, 89-94), for experts (93%; 95% CI, 91-96), and when the optical biopsy assessment was made with high confidence (93%; 95% CI, 90-96). Our meta-analyses also indicate that the agreement in assignment of postpolypectomy surveillance intervals based on optical biopsy with NBI of diminutive colorectal polyps is 90% or greater in academic settings (91%; 95% CI, 86-95), with experienced endoscopists (92%; 95% CI, 88-96) and when optical biopsy assessments are made with high confidence (91%; 95% CI, 88-95). Our systematic review and meta-analysis confirms that the thresholds established by the ASGE PIVI for real-time endoscopic assessment of the histology of diminutive polyps have been met, at least with NBI optical biopsy, with endoscopists who are expert in using this advanced imaging technology and when assessments are made with high confidence.

  View details for DOI 10.1016/j.gie.2014.12.022

  View details for PubMedID 25597420

• The optimal interval of endoscopic variceal ligation: an issue of controversy Response GASTROINTESTINAL ENDOSCOPY Hwang, J., Cash, B. D. 2015; 81 (3): 774-775

  View details for DOI 10.1016/j.gie.2014.09.055

  View details for Web of Science ID 000351666800044

  View details for PubMedID 25708768

• ASGE Technology Committee systematic review and meta-analysis assessing the ASGE PIVI thresholds for adopting real-time endoscopic assessment of the histology of diminutive colorectal polyps GASTROINTESTINAL ENDOSCOPY Abu Dayyeh, B. K., Thosani, N., Konda, V., Wallace, M. B., Rex, D. K., Chauhan, S. S., Hwang, J. H., Komanduri, S., Manfredi, M., Maple, J. T., Murad, F. M., Siddiqui, U. D., Banerjee, S. 2015; 81 (3): 502-502

  Abstract

  In vivo real-time assessment of the histology of diminutive (≤5 mm) colorectal polyps detected at colonoscopy can be achieved by means of an "optical biopsy" by using currently available endoscopic technologies. This systematic review and meta-analysis was performed by the American Society for Gastrointestinal Endoscopy (ASGE) Technology Committee to specifically assess whether acceptable performance thresholds outlined by an ASGE Preservation and Incorporation of Valuable endoscopic Innovations (PIVI) document for clinical adoption of these technologies have been met. We conducted direct meta-analyses calculating the pooled negative predictive value (NPV) for narrow-band imaging (NBI), i-SCAN, and Fujinon Intelligent Color Enhancement (FICE)-assisted optical biopsy for predicting adenomatous polyp histology of small/diminutive colorectal polyps. We also calculated the pooled percentage agreement with histopathology when assigning postpolypectomy surveillance intervals based on combining real-time optical biopsy of colorectal polyps 5 mm or smaller with histopathologic assessment of polyps larger than 5 mm. Random-effects meta-analysis models were used. Statistical heterogeneity was evaluated by means of I(2) statistics. Our meta-analyses indicate that optical biopsy with NBI, exceeds the NPV threshold for adenomatous polyp histology, supporting a "diagnose-and-leave" strategy for diminutive predicted nonneoplastic polyps in the rectosigmoid colon. The pooled NPV of NBI for adenomatous polyp histology by using the random-effects model was 91% (95% confidence interval [CI], 88-94). This finding was associated with a high degree of heterogeneity (I(2) = 89%). Subgroup analysis indicated that the pooled NPV was greater than 90% for academic medical centers (91.8%; 95% CI, 89-94), for experts (93%; 95% CI, 91-96), and when the optical biopsy assessment was made with high confidence (93%; 95% CI, 90-96). Our meta-analyses also indicate that the agreement in assignment of postpolypectomy surveillance intervals based on optical biopsy with NBI of diminutive colorectal polyps is 90% or greater in academic settings (91%; 95% CI, 86-95), with experienced endoscopists (92%; 95% CI, 88-96) and when optical biopsy assessments are made with high confidence (91%; 95% CI, 88-95). Our systematic review and meta-analysis confirms that the thresholds established by the ASGE PIVI for real-time endoscopic assessment of the histology of diminutive polyps have been met, at least with NBI optical biopsy, with endoscopists who are expert in using this advanced imaging technology and when assessments are made with high confidence.

  View details for DOI 10.1016/j.gie.2014.12.022

  View details for Web of Science ID 000351666800002

• Electronic chromoendoscopy GASTROINTESTINAL ENDOSCOPY Manfredi, M. A., Abu Dayyeh, B. K., Bhat, Y. M., Chauhan, S. S., Gottlieb, K. T., Hwang, J. H., Komanduri, S., Konda, V., Lo, S. K., Maple, J. T., Murad, F. M., Siddiqui, U. D., Wallace, M. B., Banerjee, S. 2015; 81 (2): 249-261

  Abstract

  Electronic chromoendoscopy technologies provide image enhancement and may improve the diagnosis of mucosal lesions. Although strides have been made in standardization of image characterization, especially with NBI, further image-to-pathology correlation and validation are required. There is promise for the development of a resect and discard policy for diminutive adenomas by using electronic chromoendoscopy; however, before this can be adopted, further community-based studies are needed. Further validated training tools for NBI, FICE, and i-SCAN will also be required for the use of these techniques to become widespread.

  View details for DOI 10.1016/j.gie.2014.06.020

  View details for Web of Science ID 000348201600001

  View details for PubMedID 25484330

• Confocal laser endomicroscopy GASTROINTESTINAL ENDOSCOPY Chauhan, S. S., Abu Dayyeh, B. K., Bhat, Y. M., Gottlieb, K. T., Hwang, J. H., Komanduri, S., Konda, V., Lo, S. K., Manfredi, M. A., Maple, J. T., Murad, F. M., Siddiqui, U. D., Banerjee, S., Wallace, M. B. 2014; 80 (6): 928-938

  View details for DOI 10.1016/j.gie.2014.06.021

  View details for Web of Science ID 000346441600002

  View details for PubMedID 25442092

• High-definition and high-magnification endoscopes GASTROINTESTINAL ENDOSCOPY Bhat, Y. M., Abu Dayyeh, B. K., Chauhan, S. S., Gottlieb, K. T., Hwang, J. H., Komanduri, S., Konda, V., Lo, S. K., Manfredi, M. A., Maple, J. T., Murad, F. M., Siddiqui, U. D., Banerjee, S., Wallace, M. B. 2014; 80 (6): 919-927

  View details for DOI 10.1016/j.gie.2014.06.019

  View details for Web of Science ID 000346441600001

  View details for PubMedID 25442091

• A New Active Cavitation Mapping Technique for Pulsed HIFU Applications-Bubble Doppler IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL Li, T., Khokhlova, T. D., Sapozhnikov, O. A., O'Donnell, M., Hwang, J. H. 2014; 61 (10): 1698-1708

  Abstract

  In this work, a new active cavitation mapping technique for pulsed high-intensity focused ultrasound (pHIFU) applications termed bubble Doppler is proposed and its feasibility is tested in tissue-mimicking gel phantoms. pHIFU therapy uses short pulses, delivered at low pulse repetition frequency, to cause transient bubble activity that has been shown to enhance drug and gene delivery to tissues. The current gold standard for detecting and monitoring cavitation activity during pHIFU treatments is passive cavitation detection (PCD), which provides minimal information on the spatial distribution of the bubbles. B-mode imaging can detect hyperecho formation, but has very limited sensitivity, especially to small, transient microbubbles. The bubble Doppler method proposed here is based on a fusion of the adaptations of three Doppler techniques that had been previously developed for imaging of ultrasound contrast agents-color Doppler, pulse-inversion Doppler, and decorrelation Doppler. Doppler ensemble pulses were interleaved with therapeutic pHIFU pulses using three different pulse sequences and standard Doppler processing was applied to the received echoes. The information yielded by each of the techniques on the distribution and characteristics of pHIFU-induced cavitation bubbles was evaluated separately, and found to be complementary. The unified approach-bubble Doppler-was then proposed to both spatially map the presence of transient bubbles and to estimate their sizes and the degree of nonlinearity.

  View details for DOI 10.1109/TUFFC.2014.006502

  View details for Web of Science ID 000345085200011

  View details for PubMedID 25265178

  View details for PubMedCentralID PMC4454370

• Technologies for monitoring the quality of endoscope reprocessing GASTROINTESTINAL ENDOSCOPY Komanduri, S., Abu Dayyeh, B. K., Bhat, Y. M., Chauhan, S. S., Gottlieb, K. T., Hwang, J. H., Konda, V., Lo, S. K., Manfredi, M., Maple, J. T., Murad, F. M., Siddiqui, U. D., Wallace, M. B., Banerjee, S. 2014; 80 (3): 369-373

  View details for DOI 10.1016/j.gie.2014.01.044

  View details for Web of Science ID 000341153400001

  View details for PubMedID 25012558

• The role of endoscopy in the management of variceal hemorrhage GASTROINTESTINAL ENDOSCOPY Hwang, J. H., Shergill, A. K., Acosta, R. D., Chandrasekhara, V., Chathadi, K. V., Decker, G. A., Early, D. S., Evans, J. A., Fanelli, R. D., Fisher, D. A., Foley, K. Q., Fonkalsrud, L., Jue, T., Khashab, M. A., Lightdale, J. R., Muthusamy, V. R., Pasha, S. F., Saltzman, J. R., Sharaf, R., Cash, B. D. 2014; 80 (2): 221-227

  View details for DOI 10.1016/j.gie.2013.07.023

  View details for Web of Science ID 000341151700002

  View details for PubMedID 25034836

• PASSIVE CAVITATION DETECTION DURING PULSED HIFU EXPOSURES OF EX VIVO TISSUES AND IN VIVO MOUSE PANCREATIC TUMORS ULTRASOUND IN MEDICINE AND BIOLOGY Li, T., Chen, H., Khokhlova, T., Wang, Y., Kreider, W., He, X., Hwang, J. H. 2014; 40 (7): 1523-1534

  Abstract

  Pulsed high-intensity focused ultrasound (pHIFU) has been shown to enhance vascular permeability, disrupt tumor barriers and enhance drug penetration into tumor tissue through acoustic cavitation. Monitoring of cavitation activity during pHIFU treatments and knowing the ultrasound pressure levels sufficient to reliably induce cavitation in a given tissue are therefore very important. Here, three metrics of cavitation activity induced by pHIFU and evaluated by confocal passive cavitation detection were introduced: cavitation probability, cavitation persistence and the level of the broadband acoustic emissions. These metrics were used to characterize cavitation activity in several ex vivo tissue types (bovine tongue and liver and porcine adipose tissue and kidney) and gel phantoms (polyacrylamide and agarose) at varying peak-rare factional focal pressures (1-12 MPa) during the following pHIFU protocol: frequency 1.1 MHz, pulse duration 1 ms and pulse repetition frequency 1 Hz. To evaluate the relevance of the measurements in ex vivo tissue, cavitation metrics were also investigated and compared in the ex vivo and in vivo murine pancreatic tumors that develop spontaneously in transgenic KrasLSL.G12 D/+; p53 R172 H/+; PdxCretg/+ (KPC) mice and closely re-capitulate human disease in their morphology. The cavitation threshold, defined at 50% cavitation probability, was found to vary broadly among the investigated tissues (within 2.5-10 MPa), depending mostly on the water-lipid ratio that characterizes the tissue composition. Cavitation persistence and the intensity of broadband emissions depended both on tissue structure and lipid concentration. Both the cavitation threshold and broadband noise emission level were similar between ex vivo and in vivo pancreatic tumor tissue. The largest difference between in vivo and ex vivo settings was found in the pattern of cavitation occurrence throughout pHIFU exposure: it was sporadic in vivo, but it decreased rapidly and stopped over the first few pulses ex vivo. Cavitation activity depended on the interplay between the destruction and circulation of cavitation nuclei, which are not only used up by HIFU treatment but also replenished or carried away by circulation in vivo. These findings are important for treatment planning and optimization in pHIFU-induced drug delivery, in particular for pancreatic tumors.

  View details for DOI 10.1016/j.ultrasmedbio.2014.01.007

  View details for Web of Science ID 000341459000019

  View details for PubMedID 24613635

  View details for PubMedCentralID PMC4048799

• Scanning fiber endoscopy: a novel platform for cholangioscopy GASTROINTESTINAL ENDOSCOPY Templeton, A. W., Webb, K., Hwang, J. H., Seibel, E. J., Saunders, M. 2014; 79 (6): 1000-1001

  View details for DOI 10.1016/j.gie.2013.12.005

  View details for Web of Science ID 000336497700018

  View details for PubMedID 24462166

• The role of endoscopy in the patient with lower GI bleeding GASTROINTESTINAL ENDOSCOPY Pasha, S. F., Shergill, A., Acosta, R. D., Chandrasekhara, V., Chathadi, K. V., Early, D., Evans, J. A., Fisher, D., Fonkalsrud, L., Hwang, J. H., Khashab, M. A., Lightdale, J. R., Muthusamy, V. R., Saltzman, J. R., Cash, B. D. 2014; 79 (6): 875-885

  View details for DOI 10.1016/j.gie.2013.10.039

  View details for Web of Science ID 000336497700001

  View details for PubMedID 24703084

• Modifications in endoscopic practice for pediatric patients GASTROINTESTINAL ENDOSCOPY Lightdale, J. R., Lightdale, J. R., Acosta, R., Shergill, A. K., Chandrasekhara, V., Chathadi, K., Early, D., Evans, J. A., Fanelli, R. D., Fisher, D. A., Fonkalsrud, L., Hwang, J. H., Kashab, M., Muthusamy, V. R., Pasha, S., Saltzman, J. R., Cash, B. D. 2014; 79 (5): 699-710

  Abstract

  We recommend that endoscopy in children be performed by pediatric-trained endoscopists whenever possible. We recommend that adult-trained endoscopists coordinate their services with pediatricians and pediatric specialists when they are needed to perform endoscopic procedures in children. We recommend that endoscopy be performed within 24 hours in symptomatic pediatric patients with known or suspected ingestion of caustic substances. We recommend emergent foreign-body removal of esophageal button batteries, as well as 2 or more rare-earth neodymium magnets. We recommend that procedural and resuscitative equipment appropriate for pediatric use should be readily available during endoscopic procedures. We recommend that personnel trained specifically in pediatric life support and airway management be readily available during sedated procedures in children. We recommend the use of endoscopes smaller than 6 mm in diameter in infants and children weighing less than 10 kg. We recommend the use of standard adult duodenoscopes for performing ERCP in children who weigh at least 10 kg. We recommend the placement of 12F or 16F percutaneous endoscopic gastrostomy tubes in children who weigh less than 50 kg.

  View details for DOI 10.1016/j.gie.2013.08.014

  View details for Web of Science ID 000334299300001

  View details for PubMedID 24593951

• The role of endoscopy in the evaluation and management of dysphagia GASTROINTESTINAL ENDOSCOPY Pasha, S. F., Acosta, R. D., Chandrasekhara, V., Chathadi, K. V., Decker, G. A., Early, D. S., Evans, J. A., Fanelli, R. D., Fisher, D. A., Foley, K. Q., Fonkalsrud, L., Hwang, J. H., Jue, T. L., Khashab, M. A., Lightdale, J. R., Muthusamy, V. R., Sharaf, R., Saltzman, J. R., Shergill, A. K., Cash, B. 2014; 79 (2): 191-201

  View details for DOI 10.1016/j.gie.2013.07.042

  View details for Web of Science ID 000329759200001

  View details for PubMedID 24332405

• Gastric Cancer in Asian American Populations: a Neglected Health Disparity ASIAN PACIFIC JOURNAL OF CANCER PREVENTION Taylor, V. M., Ko, L. K., Hwang, J. H., Sin, M., Inadomi, J. M. 2014; 15 (24): 10565-10571

  Abstract

  Gastric cancer incidence rates vary dramatically by world region with East Asia having the highest rate. The Asian population of the United States (US) is growing rapidly and over 17 million Americans are of Asian descent. A majority of Chinese, Korean and Vietnamese Americans are immigrants. Americans of East and Southeast Asian descent experience marked gastric cancer disparities and the incidence rate among Korean men in the US is over five times higher than the incidence rate among non-Hispanic white men. Randomized controlled trials have provided evidence for the effectiveness of helicobacter pylori identification and eradication in preventing gastric cancer. Additionally, Japan and South Korea have both experienced improvements in gastric cancer mortality following the implementation of programs to detect early stage gastric cancers. There are currently no clear US guidelines regarding the primary and secondary prevention of gastric cancer in high-risk immigrant populations. However, it is likely that a proportion of US physicians are already recommending gastric cancer screening for Asian patients and some Asian immigrants to the US may be completing screening for gastric cancer in their native countries. Surveys of US primary care physicians and Asian American communities should be conducted to assess current provider practices and patient uptake with respect to gastric cancer prevention and control. In the absence of clinical guidelines, US health care providers who serve high-risk Asian groups could consider a shared decision-making approach to helicobacter pylori identification and eradication, as well as gastric endoscopy.

  View details for DOI 10.7314/APJCP.2014.15.24.10565

  View details for Web of Science ID 000351058900003

  View details for PubMedID 25605140

• Endoscopic ultrasound-guided tumor ablation Gastrointest Interv Ende, A. R., Hwang, J. 2014; 3: 27-29
• A pilot study of in vivo identification of pancreatic cystic neoplasms with needle-based confocal laser endomicroscopy under endosonographic guidance ENDOSCOPY Konda, V. J., Meining, A., Jamil, L. H., Giovannini, M., Hwang, J. H., Wallace, M. B., Chang, K. J., Siddiqui, U. D., Hart, J., Lo, S. K., Saunders, M. D., Aslanian, H. R., Wroblewski, K., Waxman, I. 2013; 45 (12): 1006-1013

  Abstract

  Endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) of pancreatic cystic lesions (PCL) is flawed by inadequate diagnostic yield. Needle-based confocal laser endomicroscopy (nCLE) utilizes a sub-millimeter probe that is compatible with an EUS needle and enables real-time imaging with microscopic detail of PCL. The aims of the In vivo nCLE Study in the Pancreas with Endosonography of Cystic Tumors (INSPECT) pilot study were to assess both the diagnostic potential of nCLE in differentiating cyst types and the safety of the technique.Eight referral centers performed nCLE in patients with PCL. Stage 1 defined descriptive terms for structures visualized by an off-line, unblinded consensus review. Cases were reviewed with a gastrointestinal pathologist to identify correlations between histology and nCLE. Stage 2 assessed whether the specific criteria defined in Stage 1 could identify pancreatic cystic neoplasms (PCN) including intraductal papillary mucinous neoplasms, mucinous cystic adenoma, or adenocarcinoma in an off-line blinded consensus review.A total of 66 patients underwent nCLE imaging and images were available for 65, 8 of which were subsequently excluded due to insufficient information for consensus reference diagnosis. The presence of epithelial villous structures based on nCLE was associated with PCN (P=0.004) and provided a sensitivity of 59%, specificity of 100%, positive predictive value of 100 %, and negative predictive value of 50%. The overall complication rate was 9% and included pancreatitis (1 mild case, 1 moderate case), transient abdominal pain (n=1), and intracystic bleeding not requiring any further measures (n=3).These preliminary data suggested that nCLE has a high specificity in the detection of PCN, but may be limited by a low sensitivity. The safety of nCLE requires further evaluation.

  View details for DOI 10.1055/s-0033-1344714

  View details for Web of Science ID 000327471700005

  View details for PubMedID 24163192

• Endoscopic Ultrasound-Fine Needle Aspiration versus Core Biopsy for the Diagnosis of Subepithelial Tumors. Clinical endoscopy Webb, K., Hwang, J. H. 2013; 46 (5): 441-444

  Abstract

  Subepithelial lesions are frequently encountered and remain a diagnostic challenge. Imaging of subepithelial lesions using endoscopic ultrasound (EUS) can be helpful in narrowing the differential diagnosis of the lesion; however, definitive diagnosis typically requires tissue. Many methods for acquiring tissue exist including EUS-guided fine needle aspiration, Trucut biopsy, and fine needle biopsy. Obtaining adequate tissue is important for cytologic and histologic exams including immunohistochemical stains, thus a great deal of effort has been made to increase tissue acquisition in order to improve diagnostic yield in subepithelial lesions.

  View details for DOI 10.5946/ce.2013.46.5.441

  View details for PubMedID 24143299

  View details for PubMedCentralID PMC3797922

• Confocal Microscopy in the Esophagus and Stomach CLINICAL ENDOSCOPY Templeton, A., Hwang, J. 2013; 46 (5): 445-449

  Abstract

  Probe-based confocal microscopy (pCLE) is actively being investigated for applications in the esophagus and stomach. The use of pCLE allows real-time in vivo microscopy to evaluate the microarchitecture of the mucosal epithelium. pCLE appears to be particularly useful in identifying mucosal dysplasia and early malignancies that cannot be clearly distinguished using high-definition white light endoscopy, chromoendoscopy, or magnification endoscopy. In addition, the ability to detect dysplastic tissue in real-time may shift the current screening practice from random biopsy to targeted biopsy of esophageal and gastric cancers and their precursor lesions. We will review the use of pCLE for detection and surveillance of upper gastrointestinal early luminal malignancy.

  View details for DOI 10.5946/ce.2013.46.5.445

  View details for Web of Science ID 000409983500004

  View details for PubMedID 24143300

  View details for PubMedCentralID PMC3797923

• The use of twinkling artifact of Doppler imaging to monitor cavitation in tissue during high intensity focused ultrasound therapy. Proceedings of meetings on acoustics . Acoustical Society of America Khokhlova, T., Li, T., Sapozhnikov, O., Hwang, J. H. 2013; 19 (1)

  Abstract

  In high intensity focused ultrasound (HIFU) therapy, it is important to monitor the presence and activity of microbubbles in tissue during treatment. The current methods, - passive cavitation detection (PCD) and B-mode imaging - have limited sensitivity, especially to small-size, non-violently-collapsing microbubbles. Here, a new method for microbubble detection is proposed, based on "twinkling" artifact (TA) of Doppler imaging. TA occurs when Color Doppler ultrasound is used to image hard objects in tissue (e.g., kidney stones), and is displayed as brightly colored spots. As demonstrated recently, TA can be explained by irregular scattering of the Doppler ensemble pulses from the fluctuating microbubbles trapped in crevices of the kidney stone. In this work, TA was used to detect cavitation in tissue and in polyacrylamide gel phantoms during pulsed 1 MHz HIFU exposures with different peak negative pressures (1.5-11 MPa). At each pressure level, the probability of cavitation occurrence was characterized using TA and the broadband signals recorded by PCD, aligned confocally with the HIFU transducer. The results indicate that TA is more sensitive to the onset of cavitation than conventional PCD detection, and allows for accurate spatial localization of the bubbles. Work supported by RFBR and NIH (EB007643, 1K01EB015745, R01CA154451).

  View details for PubMedID 26185591

  View details for PubMedCentralID PMC4501386

• HISTOLOGICAL AND BIOCHEMICAL ANALYSIS OF MECHANICAL AND THERMAL BIOEFFECTS IN BOILING HISTOTRIPSY LESIONS INDUCED BY HIGH INTENSITY FOCUSED ULTRASOUND ULTRASOUND IN MEDICINE AND BIOLOGY Wang, Y., Khokhlova, T., Bailey, M., Hwang, J. H., Khokhlova, V. 2013; 39 (3): 424-438

  Abstract

  Recent studies have shown that shockwave heating and millisecond boiling in high-intensity focused ultrasound fields can result in mechanical fractionation or emulsification of tissue, termed boiling histotripsy. Visual observations of the change in color and contents indicated that the degree of thermal damage in the emulsified lesions can be controlled by varying the parameters of the exposure. The goal of this work was to examine thermal and mechanical effects in boiling histotripsy lesions using histologic and biochemical analysis. The lesions were induced in ex vivo bovine heart and liver using a 2-MHz single-element transducer operating at duty factors of 0.005-0.01, pulse durations of 5-500 ms and in situ shock amplitude of 73 MPa. Mechanical and thermal damage to tissue was evaluated histologically using conventional staining techniques (hematoxylin and eosin, and nicotinamide adenine dinucleotide-diaphorase). Thermal effects were quantified by measuring denaturation of salt soluble proteins in the treated region. According to histologic analysis, the lesions that visually appeared as a liquid contained no cellular structures larger than a cell nucleus and had a sharp border of one to two cells. Both histologic and protein analysis showed that lesions obtained with short pulses (<10 ms) did not contain any thermal damage. Increasing the pulse duration resulted in an increase in thermal damage. However, both protein analysis and nicotinamide adenine dinucleotide-diaphorase staining showed less denaturation than visually observed as whitening of tissue. The number of high-intensity focused ultrasound pulses delivered per exposure did not change the lesion shape or the degree of thermal denaturation, whereas the size of the lesion showed a saturating behavior suggesting optimal exposure duration. This study confirmed that boiling histotripsy offers an effective, predictable way to non-invasively fractionate tissue into sub-cellular fragments with or without inducing thermal damage.

  View details for DOI 10.1016/j.ultrasmedbio.2012.10.012

  View details for Web of Science ID 000314872200007

  View details for PubMedID 23312958

  View details for PubMedCentralID PMC3570648

• The road to clinical use of high-intensity focused ultrasound for liver cancer: technical and clinical consensus. Journal of therapeutic ultrasound Aubry, J., Pauly, K. B., Moonen, C., Haar, G. t., Ries, M., Salomir, R., Sokka, S., Sekins, K. M., Shapira, Y., Ye, F., Huff-Simonin, H., Eames, M., Hananel, A., Kassell, N., Napoli, A., Hwang, J. H., Wu, F., Zhang, L., Melzer, A., Kim, Y., Gedroyc, W. M. 2013; 1: 13-?

  Abstract

  Clinical use of high-intensity focused ultrasound (HIFU) under ultrasound or MR guidance as a non-invasive method for treating tumors is rapidly increasing. Tens of thousands of patients have been treated for uterine fibroid, benign prostate hyperplasia, bone metastases, or prostate cancer. Despite the methods' clinical potential, the liver is a particularly challenging organ for HIFU treatment due to the combined effect of respiratory-induced liver motion, partial blocking by the rib cage, and high perfusion/flow. Several technical and clinical solutions have been developed by various groups during the past 15 years to compensate for these problems. A review of current unmet clinical needs is given here, as well as a consensus from a panel of experts about technical and clinical requirements for upcoming pilot and pivotal studies in order to accelerate the development and adoption of focused ultrasound for the treatment of primary and secondary liver cancer.

  View details for DOI 10.1186/2050-5736-1-13

  View details for PubMedID 25512859

• Ultrasound-targeted microbubble destruction for chemotherapeutic drug delivery to solid tumors. Journal of therapeutic ultrasound Chen, H., Hwang, J. H. 2013; 1: 10-?

  Abstract

  Ultrasound-targeted microbubble destruction (UTMD) is a promising technique for non-invasive, targeted drug delivery, and its applications in chemotherapeutic drug delivery to solid tumors have attracted growing interest. Ultrasound, which has been conventionally used for diagnostic imaging, has evolved as a promising tool for therapeutic applications mainly because of its ability to be focused deep inside the human body, providing a modality for targeted delivery. Although originally being introduced into clinics as ultrasound contrast agents, microbubbles (MBs) have been developed as a diagnostic and therapeutic agent that can both be tracked through non-invasive imaging and deliver therapeutic agents selectively at ultrasound-targeted locations. Whereas free drugs often possess harmful side effects, their encapsulation in MBs and subsequent local release at the targeted tissue by ultrasound triggering may help improve the margin of safety. In the past 10 years, the feasibility and safety of UTMD have been extensively tested using normal animal models. Most recently, a growing number of preclinical studies have been reported on the therapeutic benefits of UTMD in the delivery of chemotherapeutic drugs to various malignant tumors, such as brain, liver, eyelid, pancreas, and breast tumors. Increased drug concentration in tumors and reduced tumor sizes were achieved in those tumors treated with UTMD in combination with chemotherapeutic drugs, when compared to tumors treated with chemotherapy drugs alone. This review presents an overview of current preclinical applications of UTMD in chemotherapeutic drug delivery for the treatment of cancers along with a discussion of its future developments.

  View details for DOI 10.1186/2050-5736-1-10

  View details for PubMedID 25512858

  View details for PubMedCentralID PMC4265893

• Controllable in vivo hyperthermia effect induced by pulsed high intensity focused ultrasound with low duty cycles APPLIED PHYSICS LETTERS Tu, J., Hwang, J. H., Chen, T., Fan, T., Guo, X., Crum, L. A., Zhang, D. 2012; 101 (12)

  Abstract

  High intensity focused ultrasound (HIFU)-induced hyperthermia is a promising tool for cancer therapy. Three-dimensional nonlinear acoustic-bioheat transfer-blood flow-coupling model simulations and in vivo thermocouple measurements were performed to study hyperthermia effects in rabbit auricular vein exposed to pulsed HIFU (pHIFU) at varied duty cycles (DCs). pHIFU-induced temperature elevations are shown to increase with increasing DC. A critical DC of 6.9% is estimated for temperature at distal vessel wall exceeding 44 °C, although different tissue depths and inclusions could affect the DC threshold. The results demonstrate clinic potentials of achieving controllable hyperthermia by adjusting pHIFU DCs, while minimizing perivascular thermal injury.

  View details for DOI 10.1063/1.4754113

  View details for Web of Science ID 000309425700105

  View details for PubMedID 23112347

• Multicenter, randomized, controlled trial of confocal laser endomicroscopy assessment of residual metaplasia after mucosal ablation or resection of GI neoplasia in Barrett's esophagus GASTROINTESTINAL ENDOSCOPY Wallace, M. B., Crook, J. E., Saunders, M., Lovat, L., Coron, E., Waxman, I., Sharma, P., Hwang, J. H., Banks, M., Depreville, M., Galmiche, J. P., Konda, V., Diehl, N. N., Wolfsen, H. C. 2012; 76 (3): 539-?

  Abstract

  Endoscopic ablation is an accepted standard for neoplasia in Barrett's esophagus (BE). Eradication of all glandular mucosa in the distal esophagus cannot be reliably determined at endoscopy.To assess if use of probe-based confocal laser endomicroscopy (pCLE) in addition to high-definition white light (HDWL) could aid in determination of residual BE.Prospective, multicenter, randomized, clinical trial.Academic medical centers.Patients with Barrett's esophagus undergoing ablation.After an initial attempt at ablation, patients were followed-up either with HDWL endoscopy or HDWL plus pCLE, with treatment of residual metaplasia or neoplasia based on endoscopic findings and pCLE used to avoid overtreatment.The proportion of optimally treated patients, defined as those with residual BE who were treated and had complete ablation plus those without BE who were not treated and had no evidence of disease at follow-up.The study was halted at the planned interim analysis based on a priori criteria. After enrollment was halted, all patients who had been randomized were followed to study completion. Among the 119 patients with follow-up, there was no difference in the proportion of patients achieving optimal outcomes in the two groups (15/57, 26% for HDWL; 17/62, 27% with HDWL + pCLE). Other outcomes were similar in the two groups.The study was closed after the interim analysis due to low conditional power resulting from lack of difference between groups as well as higher-than-expected residual Barrett's esophagus in both arms.This study yields no evidence that the addition of pCLE to HDWL imaging for detection of residual Barrett's esophagus or neoplasia can provide improved treatment.

  View details for DOI 10.1016/j.gie.2012.05.004

  View details for Web of Science ID 000307948600013

  View details for PubMedID 22749368

• In vivo hyperthermia effect induced by high-intensity pulsed ultrasound CHINESE PHYSICS B Cui, W., Tu, J., Hwang, J., Li, Q., Fan, T., Zhang, D., Chen, J., Chen, W. 2012; 21 (7)

  View details for DOI 10.1088/1674-1056/21/7/074301

  View details for Web of Science ID 000306558300054

• The role of endoscopy in the management of acute non-variceal upper GI bleeding GASTROINTESTINAL ENDOSCOPY Hwang, J. H., Fisher, D. A., Ben-Menachem, T., Chandrasekhara, V., Chathadi, K., Decker, G. A., Early, D. S., Evans, J. A., Fanelli, R. D., Foley, K., Fukami, N., Jain, R., Jue, T. L., Khan, K. M., Lightdale, J., Malpas, P. M., Maple, J. T., Pasha, S., Saltzman, J., Sharaf, R., Shergill, A. K., Dominitz, J. A., Cash, B. D. 2012; 75 (6): 1132-1138

  View details for DOI 10.1016/j.gie.2012.02.033

  View details for Web of Science ID 000305453700002

  View details for PubMedID 22624808

• Appropriate use of GI endoscopy GASTROINTESTINAL ENDOSCOPY Early, D. S., Ben-Menachem, T., Decker, G., Evans, J. A., Fanelli, R. D., Fisher, D. A., Fukami, N., Hwang, J., Jain, R., Jue, T. L., Khan, K. M., Malpas, P. M., Maple, J. T., Sharaf, R. S., Dominitz, J. A., Cash, B. D., ASGE Stand Practice Comm 2012; 75 (6): 1127-1131

  View details for DOI 10.1016/j.gie.2012.01.011

  View details for Web of Science ID 000305453700001

  View details for PubMedID 22624807

• TARGETED LONG-TERM VENOUS OCCLUSION USING PULSED HIGH-INTENSITY FOCUSED ULTRASOUND COMBINED WITH A PRO-INFLAMMATORY AGENT ULTRASOUND IN MEDICINE AND BIOLOGY Zhou, Y., Zia, J., Warren, C., Starr, F. L., Brayman, A. A., Crum, L. A., Hwang, J. H. 2011; 37 (10): 1653-1658

  Abstract

  Esophageal and gastric varices are associated with significant morbidity and mortality for cirrhotic patients. The current modalities available for treating bleeding esophageal and gastric varices, namely endoscopic band ligation and sclerotherapy, require frequent sessions to obtain effective thrombosis and are associated with significant adverse effects. A more effective therapy that results in long-term vascular occlusion has the potential to improve patient outcomes. In this study, we investigated a new potential method for inducing long-term vascular occlusion by targeting segments of a rabbit's auricular vein in vivo with low-duty-cycle, high-peak-rarefaction pressure (9 MPa), pulsed high-intensity focused ultrasound in the presence of intravenously administered ultrasound microbubbles followed by local injection of fibrinogen and a pro-inflammatory agent (ethanol, cyanoacrylate or morrhuate sodium). The novel method introduced in this study resulted in acute and long-term complete vascular occlusions when injecting a pro-inflammatory agent with fibrinogen. Future investigation and translational studies are needed to assess its clinical applicability.

  View details for DOI 10.1016/j.ultrasmedbio.2011.06.007

  View details for Web of Science ID 000295541600013

  View details for PubMedID 21821352

• Assessment of a simple, novel endoluminal method for gastrotomy closure in NOTES SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES Lee, S. S., Oelschlager, B. K., Wright, A. S., Soares, R. V., Sinan, H., Montenovo, M. I., Hwang, J. H. 2011; 25 (10): 3448-3452

  Abstract

  A reliable method for gastrotomy closure in NOTES will be essential for NOTES to become viable clinically. However, methods using existing and widely available endoscopic accessories have been ineffective. The objective of this study was to evaluate the feasibility and safety of a new simple method for gastric closure (retracted clip-assisted loop closure) that uses existing endoscopic accessories with minor modifications.The retracted clip-assisted loop closure technique involves deploying 3-4 Resolution(®) clips (modified by attaching a 90-cm length of suture to the end of each clip) along the margin of the gastrotomy with one jaw on the serosal surface and the other jaw on the mucosal surface. The suture strings are threaded through an endoloop. Traction is then applied to the strings causing the gastric wall to tent. The endoloop is secured below the tip of the clips, completing a full-thickness gastrotomy closure. The main outcome measures were feasibility, efficacy, and safety of the new retracted clip-assisted loop closure technique for NOTES gastrotomy closure.An air-tight seal was achieved in 100% (n = 9) of stomachs. The mean leak pressure was 116.3 (±19.4) mmHg.The retracted clip-assisted loop closure technique can be used to perform NOTES gastrotomy closure by using existing endoscopic accessories with minor modifications.

  View details for DOI 10.1007/s00464-011-1730-1

  View details for Web of Science ID 000294964600052

  View details for PubMedID 21556990

• THE EFFECT OF THE SCANNING PATHWAY IN HIGH-INTENSITY FOCUSED ULTRASOUND THERAPY ON LESION PRODUCTION ULTRASOUND IN MEDICINE AND BIOLOGY Zhou, Y., Kargl, S. G., Hwang, J. H. 2011; 37 (9): 1457-1468

  Abstract

  Because tumors are much larger in size compared with the beam width of high-intensity focused ultrasound (HIFU), raster scanning throughout the entire target is conventionally performed for HIFU thermal ablation. Thermal diffusion affects the temperature elevation and the consequent lesion formation. As a result, the lesion will grow continuously over the course of HIFU therapy. The purpose of this study was to investigate the influence of scanning pathways on the overall thermal lesion. Two new scanning pathways, spiral scanning from the center to the outside and spiral scanning from the outside to the center, were proposed with the same HIFU parameters (power and exposure time) for each treatment spot. The lesions produced in the gel phantom and bovine liver were compared with those using raster scanning. Although more uniform lesions can be achieved using the new scanning pathways, the produced lesion areas (27.5 ± 12.3 mm(2) and 65.2 ± 9.6 mm(2), respectively) in the gel phantom are significantly smaller (p < 0.05) than those using raster scanning (92.9 ± 11.8 mm(2)). Furthermore, the lesion patterns in the gel phantom and bovine liver were similar to the simulations using temperature and thermal dose-threshold models, respectively. Thermal diffusion, the scanning pathway and the biophysical aspects of the target all play important roles in HIFU lesion production. By selecting the appropriate scanning pathway and varying the parameters as ablation progresses, HIFU therapy can achieve uniform lesions while minimizing the total delivered energy and treatment time.

  View details for DOI 10.1016/j.ultrasmedbio.2011.05.848

  View details for Web of Science ID 000293449400012

  View details for PubMedID 21775048

• Confocal endomicroscopic evaluation of colorectal squamous metaplasia and dysplasia in ulcerative colitis GASTROINTESTINAL ENDOSCOPY Lord, J. D., Upton, M. P., Hwang, J. 2011; 73 (5): 1064-1066

  View details for DOI 10.1016/j.gie.2010.09.002

  View details for Web of Science ID 000290292800047

  View details for PubMedID 21067733

  View details for PubMedCentralID PMC4360953

• Barrett's esophagus: surveillance and reversal 10th World Congress of the World Organization for Specialized Studies on Diseases of the Esophagus (OESO) Caygill, C. P., Dvorak, K., Triadafilopoulos, G., Felix, V. N., Horwhat, J. D., Hwang, J. H., Upton, M. P., Li, X., Nandurkar, S., Gerson, L. B., Falk, G. W. BLACKWELL SCIENCE PUBL. 2011: 196–209

  Abstract

  The following on surveillance and reversal of Barrett's esophagus (BE) includes commentaries on criteria for surveillance even when squamous epithelium stains normally with a variety of biomarkers; the long-term follow-up of surgery versus endoscopic ablation of BE; the recommended surveillance intervals in patients without dysplasia; the sampling problems related to anatomic changes following fundoplication; the value of tissue spectroscopy and optical coherence tomography; the cost-effectiveness of biopsy protocols for surveillance; the quality of life of Barrett's patients; and risk stratification and surveillance strategies.

  View details for DOI 10.1111/j.1749-6632.2011.06052.x

  View details for Web of Science ID 000301188400012

  View details for PubMedID 21950814

• High-Intensity Focused Ultrasound to Treat Primary Hyperparathyroidism: A Feasibility Study in Four Patients AMERICAN JOURNAL OF ROENTGENOLOGY Kovatcheva, R. D., Vlahov, J. D., Shinkov, A. D., Borissova, A., Hwang, J., Arnaud, F., Hegedus, L. 2010; 195 (4): 830-835

  Abstract

  Many patients with primary hyperparathyroidism either decline or are not candidates for surgical parathyroidectomy. There are drawbacks to medical therapy as well as percutaneous ethanol injection as alternative therapies for primary hyperparathyroidism. Therefore, in this pilot study, our aim was to test the feasibility, safety, and efficacy of a newly developed noninvasive high-intensity focused ultrasound (HIFU) technique for the nonsurgical management of primary hyperparathyroidism.We treated four menopausal women with biochemical, sonographic, and cytologic evidence of benign primary hyperparathyroidism. HIFU treatment was performed in two sessions using TH-One under sonographic guidance and with the patient under conscious sedation. Parathyroid volume and function were evaluated at baseline and repeatedly until 12 months after the second HIFU session.Serum parathyroid hormone levels decreased in all four patients and normalized 1 and 8 months after the second HIFU session in two patients. Serum calcium levels decreased in all patients and normalized in three patients. Three of four parathyroid tumors had decreased in size by 11%, 43%, and 79%, respectively, 12 months after the second HIFU session. All adverse events related to HIFU were transient: mild subcutaneous edema in three patients and impaired vocal cord mobility in one patient that resolved 40 days later.HIFU is a promising procedure for patients with primary hyperparathyroidism that may become an alternative to established options, especially in elderly patients with comorbidities, or in patients who decline surgery. Large-scale long-term studies including patients with secondary and tertiary hyperparathyroidism are warranted.

  View details for DOI 10.2214/AJR.09.3932

  View details for Web of Science ID 000282033600005

  View details for PubMedID 20858805

• Current and Future Clinical Applications of High-Intensity Focused Ultrasound (HIFU) for Pancreatic Cancer GUT AND LIVER Jang, H. j., Lee, J., Lee, D., Kim, W., Hwang, J. H. 2010; 4: S57-S61

  Abstract

  High-intensity focused ultrasound (HIFU) is a novel therapeutic modality that permits noninvasive treatment of various benign and malignant solid tumors, including prostatic cancer, uterine fibroids, hepatic tumors, renal tumors, breast cancers, and pancreatic cancers. Several preclinical and clinical studies have investigated the safety and efficacy of HIFU for treating solid tumors, including pancreatic cancer. The results of nonrandomized studies of HIFU therapy in patients with pancreatic cancer have suggested that HIFU treatment can effectively alleviate cancer-related pain without any significant complications. This noninvasive method of delivering ultrasound energy into the body has recently been evolving from a method for purely thermal ablation to harnessing the mechanical effects of HIFU to induce a systemic immune response and to enhance targeted drug delivery. This review provides a brief overview of HIFU, describes current clinical applications of HIFU for pancreatic cancer, and discusses future applications and challenges.

  View details for DOI 10.5009/gnl.2010.4.S1.S57

  View details for Web of Science ID 000281932700009

  View details for PubMedID 21103296

• Robust High-Resolution Fine OCT Needle for Side-Viewing Interstitial Tissue Imaging IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Wu, Y., Xi, J., Huo, L., Padvorac, J., Shin, E. J., Giday, S. A., Lennon, A. M., Canto, M. I., Hwang, J. H., Li, X. 2010; 16 (4): 863-869

  View details for DOI 10.1109/JSTQE.2009.2035362

  View details for Web of Science ID 000283541100017

• Imaging of subsquamous Barrett's epithelium with ultrahigh-resolution optical coherence tomography: a histologic correlation study GASTROINTESTINAL ENDOSCOPY Cobb, M. J., Hwang, J. H., Upton, M. P., Chen, Y., Oelschlager, B. K., Wood, D. E., Kimmey, M. B., Li, X. 2010; 71 (2): 223-230

  Abstract

  Optical coherence tomography (OCT) is being developed as a potentially valuable method for high-resolution cross-sectional imaging of the esophageal mucosal and submucosal layers. One potential application of OCT imaging is to identify subsquamous Barrett's epithelium in patients who have undergone ablative therapy, which is not visible on standard endoscopic examination. However, histologic correlation confirming the ability of OCT to image subsquamous Barrett's epithelium has yet to be performed.Histologic correlation study.To perform histologic correlation of ultrahigh-resolution optical coherence tomography (UHR-OCT) imaging for identification of subsquamous Barrett's epithelium.Academic Medical Center (University of Washington, Seattle, WA).Fourteen patients with pathologic biopsy specimens, proven to be high-grade dysplasia or adenocarcinoma underwent esophagectomy.UHR-OCT imaging was performed on ex vivo esophagectomy specimens immediately after resection.Correlation of UHR-OCT images with histologic images.Subsquamous Barrett's epithelium was clearly identified by using UHR-OCT images and was confirmed by corresponding histology.Difficulty distinguishing some subsquamous Barrett's glands from blood vessels in ex vivo tissue (because of the lack of blood flow) in some cases. Imaging was performed with a bench-top system.Results from this study demonstrate that UHR-OCT imaging is capable of identifying subsquamous Barrett's epithelium.

  View details for DOI 10.1016/j.gie.2009.07.005

  View details for Web of Science ID 000274777200001

  View details for PubMedID 19846077

• Targeted Venous Occlusion Using Pulsed High-Intensity Focused Ultrasound IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING Hwang, J. H., Zhou, Y., Warren, C., Brayman, A. A., Crum, L. A. 2010; 57 (1): 37-40

  Abstract

  Targeted vascular occlusion is desirable for clinical therapies such as in the treatment of esophageal and gastric varices and varicose veins. The feasibility of ultrasound-mediated endothelial damage for vascular occlusion was studied. A segment of a rabbit auricular vein was treated in vivo with low duty cycle, high peak rarefaction pressure (9 MPa) high-intensity focused ultrasound pulses in the presence of intravenously administered circulating microbubbles, followed by fibrinogen injection, which resulted in the formation of an acute occlusive intravascular thrombus. Further investigation and refinements of treatment protocols are necessary for producing durable vascular occlusion.

  View details for DOI 10.1109/TBME.2009.2029865

  View details for Web of Science ID 000273565600009

  View details for PubMedID 19709959

• Therapeutic ultrasound: Recent trends and future perspectives Crum, L., Bailey, M., Hwang, J., Khokhlova, V., Sapozhnikov, O., Garreton, L. G. ELSEVIER SCIENCE BV. 2010: 25-34

  View details for DOI 10.1016/j.phpro.2010.01.005

  View details for Web of Science ID 000275913100003

• The Role of EUS in Subepithelial Lesions ENDOSCOPIC ULTRASOUND-BOOK Brown-Chang, J., Hwang, J., Shami, V. M., Kahaleh, M. 2010: 249-266

  View details for DOI 10.1007/978-1-60327-480-7_10

  View details for Web of Science ID 000282668200010

• To perform a biopsy or not to perform a biopsy? Does confocal endomicroscopy provide the answer for surveillance in Barrett's esophagus? GASTROINTESTINAL ENDOSCOPY Hwang, J. 2009; 70 (4): 655-657

  View details for DOI 10.1016/j.gie.2009.04.047

  View details for Web of Science ID 000270527300009

  View details for PubMedID 19788981

• High-resolution OCT balloon imaging catheter with astigmatism correction OPTICS LETTERS Xi, J., Huo, L., Wu, Y., Cobb, M. J., Hwang, J. H., Li, X. 2009; 34 (13): 1943-1945

  Abstract

  We report new optics designs for an optical coherence tomography (OCT) balloon imaging catheter to achieve diffraction-limited high resolution at a large working distance and enable the correction of severe astigmatism in the catheter. The designs employed a 1 mm diameter gradient-index lens of a properly chosen pitch number and a glass rod spacer to fully utilize the available NA of the miniature optics. Astigmatism caused by the balloon tubing was analyzed, and a method based on a cylindrical reflector was proposed and demonstrated to compensate the astigmatism. A catheter based on the new designs was successfully developed with a measured diffraction-limited lateral resolution of approximately 21 microm, a working distance of approximately 11-12 mm, and a round-shape beam profile. The performance of the OCT balloon catheter was demonstrated by 3D full-circumferential imaging of a swine esophagus in vivo along with a high-speed, Fourier-domain, mode-locked swept-source OCT system.

  View details for Web of Science ID 000268376200011

  View details for PubMedID 19571960

  View details for PubMedCentralID PMC4259896

• PRECLINICAL IN VIVO EVALUATION OF AN EXTRACORPOREAL HIFU DEVICE FOR ABLATION OF PANCREATIC TUMORS ULTRASOUND IN MEDICINE AND BIOLOGY Hwang, J. H., Wang, Y., Warren, C., Upton, M. P., Starr, F., Zhou, Y., Mitchell, S. B. 2009; 35 (6): 967-975

  Abstract

  Extracorporeal high-intensity focused ultrasound (HIFU) can be used to ablate tissue noninvasively by delivering focused ultrasound energy from an external source. HIFU for clinical treatment of pancreatic cancer has been reported; however, systematic evaluation of the safety and efficacy of pancreatic ablation with HIFU has not been performed. The objectives of this in vivo study are as follows: (1) assess the safety and feasibility of targeting and ablating pancreatic tissue using the FEP-BY02 HIFU system (Yuande Bio-Medical Engineering, Beijing, China); (2) evaluate a method for estimating in situ acoustic treatment energy in an in vivo setting; and (3) identify the optimal treatment parameters that result in safe and effective ablation of the pancreas. The pancreata of 12 common swine were treated in vivo. Prior to therapy, blood was drawn for laboratory analysis. Animals were then treated with extracorporeal HIFU at three different acoustic treatment energies (750, 1000 and 1250 J). Endoscopy was performed prior to and immediately following HIFU therapy to assess for gastric injury. Blood was drawn after completion of the treatment and on days 2 and 7 following treatment to assess for biochemical evidence of pancreatitis. Animals were then euthanized 7 d following treatment and a necropsy was performed to assess for unintended injury and to obtain pancreatic tissue for histology to assess efficacy of HIFU ablation. Histologic scoring of pancreatic tissue changes was performed by a pathologist blinded to the treatment energy delivered. The degree of ablation identified on histology correlated with the treatment energy. No collateral tissue damage was seen at treatment energies of 750 and 1000 J. At 1250 J, thermal injury to the abdominal muscles and gastric ulcers were observed. There were no premature deaths, serious illnesses, skin burns or evidence of pancreatitis on biochemical analysis. HIFU treatment of the pancreas is feasible, safe and can be used to ablate tissue noninvasively. A clinical trial in humans examining the use of extracorporeal HIFU for palliation of pain related to pancreatic cancer is planned.

  View details for DOI 10.1016/j.ultrasmedbio.2008.12.006

  View details for Web of Science ID 000267110700011

  View details for PubMedID 19201519

• Current Status of Clinical High-Intensity Focused Ultrasound 2009 ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY, VOLS 1-20 Hwang, J. H., Crum, L. A. 2009: 130-133

  Abstract

  High-intensity focused ultrasound (HIFU) is being promoted as a noninvasive method to treat certain primary solid tumors, metastatic disease, and enhance drug delivery. The field of medicine is evolving towards increasing use of noninvasive and minimally invasive therapies such as HIFU. This article provides an overview of current clinical applications of HIFU and future requirements to expand the clinical applications of this technique.

  View details for Web of Science ID 000280543600034

  View details for PubMedID 19965122

• Producing Uniform Lesion Pattern in HIFU Ablation Zhou, Y., Kargl, S. G., Hwang, J., Ebbini, E. S. AMER INST PHYSICS. 2009: 91-+

  View details for Web of Science ID 000266425300017

• Prevention of nonsteroidal anti-inflammatory drug-induced gastropathy JOURNAL OF GASTROENTEROLOGY Schlansky, B., Hwang, J. H. 2009; 44: 44-52

  Abstract

  Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for their analgesic, antipyretic, and antiinflammatory properties, and aspirin is increasingly employed in the primary and secondary prevention of cardiovascular disease and ischemic stroke. Despite undisputed therapeutic efficacy for these indications, all NSAIDs impart a considerable risk of peptic ulcer disease and upper gastrointestinal hemorrhage. A growing body of evidence supports an association between non-aspirin NSAIDs and acute coronary syndromes, and an expanding understanding of the gastroduodenal effects of aspirin, COX-2 selective agents, clopidogrel, and Helicobacter pylori synergism fuel controversies in NSAID use. In this review, we discuss risk stratification of patients taking NSAIDs and the appropriate application of proven gastro-protective strategies to decrease the incidence of gastrointestinal hemorrhage based upon an individualized assessment of risk for potential toxicities. Prevention of NSAID-related gastropathy is an important clinical issue, and therapeutic strategies for both the primary and secondary prevention of adverse events are continually evolving.

  View details for DOI 10.1007/s00535-008-2275-5

  View details for Web of Science ID 000262689000008

  View details for PubMedID 19148793

• Endomicroscopy and Biocompatible Fluorescent Nanocomplexes for Clinical Translation of High-resolution Optical Molecular Imaging 2009 IEEE/NIH LIFE SCIENCE SYSTEMS AND APPLICATIONS WORKSHOP Xi, J., Wu, Y., Kim, T. H., Chen, Y., Zheng, D., Huo, L., Cobb, M. J., Pun, S., Hwang, J. H., Li, X. 2009: 48-?

  View details for Web of Science ID 000268062300013

• Flexible miniature compound lens design for high-resolution optical coherence tomography balloon imaging catheter JOURNAL OF BIOMEDICAL OPTICS Fu, H. L., Leng, Y., Cobb, M. J., Hsu, K., Hwang, J. H., Li, X. 2008; 13 (6)

  Abstract

  We report on a new optics design for an optical coherence tomography (OCT) balloon imaging catheter. The design involves a miniature compound gradient-index (GRIN) rod lens, which consists of a fiber optic mode-field reducer and relay rod lenses to achieve predictable high lateral resolution at a desired large working distance. The compound lens design significantly simplifies the engineering process for an OCT catheter and enables 3-D full circumferential cross sectional imaging of large luminal organs such as human esophagus. An as-designed OCT catheter is developed and demonstrated for real-time in vivo swine esophagus imaging in a 3-D spiral fashion.

  View details for DOI 10.1117/1.3037340

  View details for Web of Science ID 000263100900002

  View details for PubMedID 19123643

  View details for PubMedCentralID PMC2697562

• High-resolution OCT Balloon Catheter for Systematic Imaging of the Esophagus 2007 CONFERENCE ON LASERS & ELECTRO-OPTICS/QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE (CLEO/QELS 2007), VOLS 1-5 Fu, H. L., Cobb, M. J., Leng, Y., Macdonald, D. J., Hwang, J. H., Li, X. 2007: 1660-?

  View details for Web of Science ID 000268751001272

• Intravascular inertial cavitation activity detection and quantification in vivo with optison ULTRASOUND IN MEDICINE AND BIOLOGY Tu, J., Hwang, J. H., Matula, T. J., Brayman, A. A., Crum, L. A. 2006; 32 (10): 1601-1609

  Abstract

  Inertial cavitation (IC) is an important mechanism by which ultrasound (US)-induced bioeffects can be produced. It has been reported that US-induced in vitro mechanical bioeffects with the presence of ultrasound contrast agents (UCAs) are highly correlated with quantified IC "dose" (ICD: cumulated root-mean-squared broadband noise amplitude in the frequency domain). The ICD has also been used to quantify IC activity in ex vivo perfused rabbit ear vessels. The in vivo experiments reported here using a rabbit ear vessel model were designed to: (1) detect and quantify IC activity in vivo within the constrained environment of rabbit auricular veins with the presence of Optison and (2) measure the temporal evolution of microbubble IC activity and the ICD generated during insonation treatment, as a function of acoustic parameters. Preselected regions-of-interest (ROI) in the rabbit ear vein were exposed to pulsed focused US (1.17 MHz, 1 Hz PRF). Experimental acoustic variables included peak rarefaction pressure amplitude ([PRPA]: 1.1, 3.0, 6.5 or 9.0 MPa) and pulse length (20, 100, 500 or 1000 cycles). ICD was quantified based on passive cavitation detection (PCD) measurements. The results show that: (1) after Optison injection, the time to onset of measurable microbubble IC activity was relatively consistent, approximately 20 s; (2) after reaching its peak value, the IC activity decayed exponentially and the half-life decay coefficient (t(1/2)) increased with increasing PRPA and pulse length; and (3) the normalized ICD generated by pulsed US exposure increased significantly with increasing PRPA and pulse length.

  View details for DOI 10.1016/j.ultrasmedbio.2006.07.015

  View details for Web of Science ID 000241592500019

  View details for PubMedID 17045881

• Correlation between inertial cavitation dose and endothelial cell damage in vivo ULTRASOUND IN MEDICINE AND BIOLOGY Hwang, J. H., Tu, J., Brayman, A. A., Matula, T. J., Crum, L. A. 2006; 32 (10): 1611-1619

  Abstract

  Previous in vivo studies have demonstrated that vascular endothelial damage can result when vessels containing gas-based microbubble ultrasound contrast agent (UCA) are exposed to MHz-frequency pulsed ultrasound (US) of sufficient pressure amplitudes, presumably as a result of inertial cavitation (IC). The hypothesis guiding this research was that IC is the primary mechanism by which the vascular endothelium (VE) is damaged when a vessel is exposed to pulsed 1-MHz frequency US in the presence of circulating UCA. The expectation was that a correlation should exist between the magnitude and duration of IC activity and the degree of VE damage. Rabbit auricular vessels were exposed in vivo to 1.17-MHz focused US of variable peak rarefaction pressure amplitude (1, 3, 6.5 or 9 MPa), using low duty factors (0.04% or 0.4%), pulse lengths of 500 or 5000 cycles, with varying treatment durations and with or without infusion of a shelled microbubble contrast agent. A broadband passive cavitation detection system was used to measure IC activity in vivo within the targeted segment of the blood vessel. The magnitude of the detected IC activity was quantified using a previously reported measure of IC dose. Endothelial damage was assessed via scanning electron microscopy image analysis. The results supported the hypothesis and demonstrate that the magnitude of the measured IC dose correlates with the degree of VE damage when UCA is present. These results have implications for therapeutic US-induced vascular occlusion.

  View details for DOI 10.1016/j.ultrasmedbio.2006.07.016

  View details for Web of Science ID 000241592500020

  View details for PubMedID 17045882

• American gastroenterological association institute technical review on the management of gastric subepithelial masses GASTROENTEROLOGY Hwang, J. H., Rulyak, S. D., Kimmey, M. B. 2006; 130 (7): 2217-2228

  Abstract

  This literature review and the recommendations therein were prepared for the American Gastroenterological Association Institute Clinical Practice and Economics Committee. The paper was approved by the Committee on January 19, 2006, and by the AGA Institute Governing Board on April 20, 2006.

  View details for DOI 10.1053/j.gastro.2006.04.033

  View details for Web of Science ID 000238207500028

  View details for PubMedID 16762644

• American Gastroenterological Association Institute medical position statement on the management of gastric subepithelial masses. Gastroenterology American Gastroenterological Association Institute 2006; 130 (7): 2215-6

  Abstract

  This document presents the official recommendations of the American Gastroenterological Association Institute (AGA Institute) on "Management of Gastric Subepithelial Masses." It was approved by the Clinical Practice and Economics Committee on January 19, 2006, and by the AGA Institute Governing Board on April 20, 2006.

  View details for PubMedID 16762643

• Detection of Subsquamous Barrett Epithelium Using Ultrahigh Resolution Optical Coherence Tomography Upton, M. P., Cobb, M. J., Hwang, J., Li, X., Kimmey, M. B. MOSBY-ELSEVIER. 2006: AB234

  View details for DOI 10.1016/j.gie.2006.03.600

  View details for Web of Science ID 000207499900575

• A prospective study comparing endoscopy and EUS in the evaluation of GI subepithelial masses GASTROINTESTINAL ENDOSCOPY Hwang, J. H., Saunders, M. D., Rulyak, S. J., Shaw, S., Nictsch, H., Kimmey, M. B. 2005; 62 (2): 202-208

  Abstract

  The purpose of this study is to prospectively evaluate the performance characteristics of endoscopy and EUS in the diagnosis of GI subepithelial masses.A total of 100 consecutive patients referred for the evaluation of a suspected GI subepithelial lesion were prospectively studied with endoscopy followed by EUS. Size, color, mobility, location (intramural or extramural), consistency (solid, cystic, or vascular), and presumptive diagnosis were recorded at the time of endoscopy. EUS then was performed, and size, echogenicity, location, and presumptive diagnosis were determined.A total of 100 subepithelial lesions were evaluated. Endoscopy had 98% sensitivity and 64% specificity in identifying intramural lesions. Size measurement by endoscopy correlated with size measurement by EUS (r = 0.88). Histology was obtained in 23 cases, with the presumptive EUS diagnosis correct in only 48% of cases. Most incorrect EUS diagnoses occurred with hypoechoic 3rd and 4th layer masses.Endoscopy has high sensitivity but low specificity in identifying the location (intramural or extramural) of subepithelial lesions. In addition, EUS imaging alone is insufficient to accurately diagnose 3rd and 4th layer hypoechoic masses, and histologic confirmation should be obtained whenever possible.

  View details for Web of Science ID 000231031000002

  View details for PubMedID 16046979

• Optical coherence tomography imaging of the pancreas: a needle-based approach. Clinical gastroenterology and hepatology Hwang, J. H., Cobb, M. J., Kimmey, M. B., Li, X. 2005; 3 (7): S49-52

  Abstract

  A novel, high-resolution, needle-based optical coherence tomography (OCT) device for improving the ability to detect early epithelial dysplasia in solid tissues/organs in vivo is currently in development. An instrument capable of real-time imaging of tissue microstructures in vivo could improve the ability to detect pathologic conditions such as dysplasia, and consequently improve patient outcomes. OCT is an emerging technology that can perform real-time cross-sectional imaging of tissue structures at micron-scale resolution in vivo. OCT has been shown to be effective in the imaging of luminal epithelium, capable of detecting epithelial dysplasia in Barrett's esophagus, and colonic polyps. However, OCT imaging depth with conventional probes is limited to the luminal surface (approximately 1-2 mm). The development of a technology and device that enables high-resolution, real-time imaging of solid tissues beyond 1- to 2-mm deep at or near the cellular level in vivo could improve the diagnosis of diseases of the pancreas and other solid organs.

  View details for PubMedID 16012997

• Vascular effects induced by combined 1-MHz ultrasound and microbubble contrast agent treatments in vivo ULTRASOUND IN MEDICINE AND BIOLOGY Hwang, J. H., Brayman, A. A., Reidy, M. A., Matula, T. J., Kimmey, M. B., Crum, L. A. 2005; 31 (4): 553-564

  Abstract

  Previous in vivo studies have demonstrated that microvessel hemorrhages and alterations of endothelial permeability can be produced in tissues containing microbubble-based ultrasound contrast agents when those tissues are exposed to MHz-frequency pulsed ultrasound of sufficient pressure amplitudes. The general hypothesis guiding this research was that acoustic (viz., inertial) cavitation, rather than thermal insult, is the dominant mechanism by which such effects arise. We report the results of testing five specific hypotheses in an in vivo rabbit auricular blood vessel model: (1) acoustic cavitation nucleated by microbubble contrast agent can damage the endothelia of veins at relatively low spatial-peak temporal-average intensities, (2) such damage will be proportional to the peak negative pressure amplitude of the insonifying pulses, (3) damage will be confined largely to the intimal surface, with sparing of perivascular tissues, (4) greater damage will occur to the endothelial cells on the side of the vessel distal to the source transducer than on the proximal side and (5) ultrasound/contrast agent-induced endothelial damage can be inherently thrombogenic, or can aid sclerotherapeutic thrombogenesis through the application of otherwise subtherapeutic doses of thrombogenic drugs. Auricular vessels were exposed to 1-MHz focused ultrasound of variable peak pressure amplitude using low duty factor, fixed pulse parameters, with or without infusion of a shelled microbubble contrast agent. Extravasation of Evans blue dye and erythrocytes was assessed at the macroscopic level. Endothelial damage was assessed via scanning electron microscopy (SEM) image analysis. The hypotheses were supported by the data. We discuss potential therapeutic applications of vessel occlusion, e.g., occlusion of at-risk gastric varices.

  View details for DOI 10.1016/j.ultrasmedbio.2004.12.014

  View details for Web of Science ID 000228440800011

  View details for PubMedID 15831334

• THERAPEUTIC POTENTIAL AND CONSIDERATION OF HIGH INTENSITY ULTRASOUND IN GASTROENTEROLOGY BASIC AND NEW ASPECTS OF GASTROINTESTINAL ULTRASONOGRAPHY Martin, R. W., Hwang, J., Odegaard, S., Gilja, O. H. 2005; 3: 211-236

  View details for Web of Science ID 000293009900012

• ASSESSMENT OF THE LAYERED STRUCTURE OF THE GASTROINTESTINAL TRACT BASIC AND NEW ASPECTS OF GASTROINTESTINAL ULTRASONOGRAPHY Hwang, J., Kimmey, M. B., Odegaard, S., Gilja, O. H. 2005; 3: 167-182

  View details for Web of Science ID 000293009900008

• The incidental upper gastrointestinal subepithelial mass GASTROENTEROLOGY Hwang, J. H., Kimmey, M. B. 2004; 126 (1): 301-307

  View details for DOI 10.1053/j.gastro.2003.11.040

  View details for Web of Science ID 000187803300033

  View details for PubMedID 14699508

• High-intensity focused US: a potential new treatment for GI bleeding GASTROINTESTINAL ENDOSCOPY Hwang, J. H., Vaezy, S., Martin, R. W., Cho, M. Y., Noble, M. L., Crum, L. A., Kimmey, M. B. 2003; 58 (1): 111-115

  Abstract

  High-intensity focused US has been shown to achieve hemostasis in lacerated large veins and arteries. High-intensity focused US was studied as a potential endoscopic treatment for GI bleeding.A segment of the auricular vein of the rabbit was lacerated longitudinally and then treated with a high-intensity focused US transducer driven at 3.9 MHz (focal intensity of 750 W/cm(2)) in 15 animals until hemostasis was achieved. Sham treatment was delivered to 3 vessels. Rabbits were euthanized on days 0, 2, 7, 14, and 28 to allow for histologic evaluation of the response to treatment.Hemostasis was achieved in all treated vessels and in none of the sham treatments. Mean treatment time was 13 seconds. Histology initially demonstrated acute thermal injury with subsequent thrombus formation and chronic inflammation leading to replacement of the vessel by fibrous scar tissue.High-intensity focused US causes hemostasis in acutely bleeding veins and results in occlusion of treated vessel with subsequent granulation tissue formation.

  View details for DOI 10.1067/mge.2003.322

  View details for Web of Science ID 000183971500024

  View details for PubMedID 12838236

• Race and clinical outcome in patients with carcinoma of the uterine cervix treated with radiation therapy GYNECOLOGIC ONCOLOGY Mundt, A. J., Connell, P. P., Campbell, T., Hwang, J. H., Rotmensch, J., Waggoner, S. 1998; 71 (2): 151-158

  Abstract

  The aim of this study was to examine factors underlying differences in outcome between African-American (AA) and Caucasian (C) patients undergoing radiation therapy (RT).Patient, tumor, treatment characteristics, and the outcome of 316 AA and 94 C cervical cancer patients who underwent RT were compared. Median follow-up was 72.4 months.AA patients had a trend to a poorer 8-year cause-specific survival (47.9 vs 60.6%) (P = 0.10) compared to C patients with a significant difference seen in stage IIB-IVA disease (34.3 vs 59.5%) (P = 0.04). Several factors correlated with poor outcome were present in the AA group including lower mean hemoglobin levels during RT (P = 0.001), lower median income (P = 0.001), and less frequent intracavitary RT (P = 0.09). In addition, while uncommon in C patients, health problems were major reasons for treatment protraction and inability to undergo intracavitary RT in the AA patients. Multivariate analysis demonstrated that race was not an independent prognostic factor after controlling for difference in patient, tumor, and treatment factors.AA cervical cancer patients possess multiple factors that adversely impact upon the efficacy of RT. These findings may add further insight into the observed differences in outcome of cervical cancer patients based on race.

  View details for Web of Science ID 000077351700002

  View details for PubMedID 9826453