All Publications

  • Partial versus total adrenalectomy for pheochromocytoma: a population-based comparison of outcomes. International urology and nephrology Bhambhvani, H. P., Daneshvar, M. A., Peterson, D. J., Ball, M. W. 2021


    PURPOSE: The literature assessing outcomes of partial adrenalectomy (PA) among patients with pheochromocytoma patients is largely limited to isolated, single-institution series. We aimed to perform a population-level comparison of outcomes between patients undergoing PA versus those undergoing total adrenalectomy (TA).METHODS: The Surveillance, Epidemiology, and End Results (SEER) database (1975-2016) was queried to identify adults with pheochromocytoma who underwent either PA or TA. Survival was assessed using multivariable Cox proportional hazards regression, Fine and Gray competing-risks regression, propensity score matching, Kaplan-Meier analysis, and cumulative incidence plots.RESULTS: 286 patients (PA: 101, TA: 185) were included in this study. As compared to those undergoing TA, patients undergoing PA had fewer tumors≥8cm in size (28.7% versus 42.7%, p=0.048) and were more likely to have localized disease (61.4% versus 44.3%, p=0.01). In multivariable analysis, patients undergoing PA demonstrated similar all-cause mortality (HR=0.71, 95% CI 0.44-1.14, p=0.16) and cancer-specific mortality (HR=0.64, 95% CI 0.35-1.17, p=0.15) compared to those who underwent TA. Following 1:1 propensity score matching, Kaplan-Meier analysis revealed no difference in overall survival between PA and TA groups (p=0.26) nor was there a difference in the cumulative incidence of cancer-specific mortality (p=0.29).CONCLUSIONS: In this first population-level comparison of outcomes among patients with pheochromocytoma undergoing PA and those undergoing TA, we found no long-term differences in any survival metric between groups. PA circumvents the need for lifelong corticoid replacement therapy and remains a promising option for patients with bilateral or recurrent pheochromocytoma.

    View details for DOI 10.1007/s11255-021-03004-4

    View details for PubMedID 34623590

  • Comparing Outcomes of Wise-Pattern, Two-Stage Breast Reduction-Reconstruction with and without Acellular Dermal Matrix. Plastic and reconstructive surgery Patel, A. A., Kayaleh, H., Sala, L. A., Peterson, D. J., Upadhyaya, P. K. 2021; 148 (3): 511-521


    BACKGROUND: Aesthetic results in breast reconstruction for ptotic/obese breasts may be improved when using Wise-pattern closures compared with nipple-sparing mastectomies. In two-stage reconstruction, acellular dermal matrix is commonly used to support the prosthesis. This study tests the efficacy of an alternate technique that uses deepithelialized excess breast skin in lieu of acellular dermal matrix. To better understand whether acellular dermal matrix is necessary, the authors compared postoperative outcomes from reduction-reconstructions that used matrix to those that did not.METHODS: The authors retrospectively reviewed the outcomes of patients who underwent staged breast reconstruction following Wise-pattern closures between September of 2016 and October of 2019. Two cohorts were created based on whether acellular dermal matrix was used. Charts were reviewed for incidence of postoperative complications.RESULTS: A total of 164 breasts were reconstructed in 85 female patients. The acellular dermal matrix cohort consisted of 68 breasts, whereas the non-acellular dermal matrix cohort included 96 breasts. After the first stage, the incidence of one or more complications was similar between cohorts (acellular dermal matrix, 32.4 percent; nonmatrix, 35.4 percent; p = 0.684). Minor infection rates were significantly higher in reconstructions using acellular dermal matrix (16.2 percent versus 6.3 percent; p = 0.040). After the second stage, the complication incidence was also similar between cohorts (acellular dermal matrix, 16.2 percent; nonmatrix, 13.5 percent; p = 0.638). Final follow-up time was 445.2 days.CONCLUSIONS: Overall complication rates following both stages of reconstruction were similar with and without acellular dermal matrix. When acellular dermal matrix was used, minor infection rates were higher following expander placement. In patients desiring a reduction-reconstruction, the authors find the deepithelialized dermal flap provides ample prosthesis support, without the need for acellular dermal matrix..CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

    View details for DOI 10.1097/PRS.0000000000008298

    View details for PubMedID 34432681

  • Identification of patients at high risk for preventable emergency department visits and inpatient admissions after starting chemotherapy: Machine learning applied to comprehensive electronic health record data. Peterson, D. J., Ostberg, N. P., Blayney, D. W., Brooks, J. D., Hernandez-Boussard, T. LIPPINCOTT WILLIAMS & WILKINS. 2021
  • Assessing abdominoplasty aesthetics in women with eye-tracking technology-do patients see things differently? EUROPEAN JOURNAL OF PLASTIC SURGERY Peterson, D. J., Gkorila, A., Azad, A. D., Patel, A. A., Boudreault, D. J., Nazerali, R. S. 2021
  • Machine Learning Applied to Electronic Health Records: Identification of Chemotherapy Patients at High Risk for Preventable Emergency Department Visits and Hospital Admissions. JCO clinical cancer informatics Peterson, D. J., Ostberg, N. P., Blayney, D. W., Brooks, J. D., Hernandez-Boussard, T. 2021; 5: 1106-1126


    Acute care use (ACU) is a major driver of oncologic costs and is penalized by a Centers for Medicare & Medicaid Services quality measure, OP-35. Targeted interventions reduce preventable ACU; however, identifying which patients might benefit remains challenging. Prior predictive models have made use of a limited subset of the data in the electronic health record (EHR). We aimed to predict risk of preventable ACU after starting chemotherapy using machine learning (ML) algorithms trained on comprehensive EHR data.Chemotherapy patients treated at an academic institution and affiliated community care sites between January 2013 and July 2019 who met inclusion criteria for OP-35 were identified. Preventable ACU was defined using OP-35 criteria. Structured EHR data generated before chemotherapy treatment were obtained. ML models were trained to predict risk for ACU after starting chemotherapy using 80% of the cohort. The remaining 20% were used to test model performance by the area under the receiver operator curve.Eight thousand four hundred thirty-nine patients were included, of whom 35% had preventable ACU within 180 days of starting chemotherapy. Our primary model classified patients at risk for preventable ACU with an area under the receiver operator curve of 0.783 (95% CI, 0.761 to 0.806). Performance was better for identifying admissions than emergency department visits. Key variables included prior hospitalizations, cancer stage, race, laboratory values, and a diagnosis of depression. Analyses showed limited benefit from including patient-reported outcome data and indicated inequities in outcomes and risk modeling for Black and Medicaid patients.Dense EHR data can identify patients at risk for ACU using ML with promising accuracy. These models have potential to improve cancer care outcomes, patient experience, and costs by allowing for targeted, preventative interventions.

    View details for DOI 10.1200/CCI.21.00116

    View details for PubMedID 34752139

  • Assessing Gaze Patterns in Common Cosmetic Procedures With Eye-Tracking Technology. Annals of plastic surgery Peterson, D. J., Azad, A. D., Gkorila, A. n., Patel, A. A., Boudreault, M. S., Nazerali, R. S. 2020; 84 (5S Suppl 4): S268–S272


    Understanding the salient features that draw focus when assessing aesthetics is important for maximizing perceived outcomes. Eye-tracking technology provides an unbiased method for determining the features that draw attention when evaluating aesthetic plastic surgery. This study aimed to characterize viewing patterns of plastic surgery patients and laypeople when assessing facial cosmetic procedure images.Twenty women who previously underwent cosmetic procedures and twenty women without a history of cosmetic procedures were shown sixteen pairs of preprocedure and postprocedure images of patients who underwent laser resurfacing or lip augmentation. Image pairs were randomized to whether preprocedural or postprocedural images came first. Participants viewed each image until they decided upon an aesthetic rating (scored 1-10), while an eye-tracking device recorded participants' gaze.The patient group's average ratings were 8.2% higher for preprocedural images and 13.3% higher for postprocedural images (P < 0.05 for both). The patient group spent 20.4% less time viewing images but spent proportionally more time evaluating the relevant features of each procedure (41.7% vs 23.3%, P < 0.01), such as the vermillion border of the upper lip, labial commissure, or periorbital region (P < 0.05 for each). For both groups, the most common site of first fixation was the nose for laser resurfacing images (26.6%) and the labial commissure for lip augmentation images (37.7%). Both groups spent more time fixated on nasolabial folds, marionette lines, and the periorbital region when viewing pre-laser resurfacing images than postprocedural images. Overall, each group had similar viewing patterns for time to first fixation on and frequency of fixations for a particular feature.Women who previously underwent cosmetic procedures view postprocedural images more favorably and require less time to assess images, likely related to familiarity with aesthetic procedures. These women spend more time fixated on relevant features, such as the vermillion border of the upper lip, the labial commissure, and the periorbital region, than the control group. Notably, each group spent less time focused on regions associated with wrinkles, such as the marionette and periorbital areas in post-laser resurfacing images, suggesting that the procedure reduces attention-drawing features in these areas.

    View details for DOI 10.1097/SAP.0000000000002387

    View details for PubMedID 32294074