Honors & Awards
2023 SCI Fellowship Awards, The Stanford Cancer Institute (SCI) Fellowship Awards for the Next Generation Cancer Researchers (2023)
Education Award, The International Association for the Study of Lung Cancer (IASLC) 2022 North America Conference (2022)
The Scholar-in-Training Award, The American Association for Cancer Research 2022: Precision Prevention of Cancer (2022)
Paper Competition Award, The International Conference on the 23rd Annual Meeting of the Korean Society of Cancer Prevention (2018)
Academic Excellence Scholarship, National Cancer Center Korea (2017-2019)
Academic Excellence Scholarship, National Cancer Center Korea (2014-2015)
Dean's Award, Emory University (2011)
Boards, Advisory Committees, Professional Organizations
Member, American Statistical Association (ASA) (2022 - Present)
Member, Society for Epidemiologic Research (SER) (2022 - Present)
Member, International Association for the Study of Lung Cancer (IASLC) (2022 - Present)
Member, American Association for Cancer Research (AACR) (2021 - Present)
Doctor of Philosophy, National Cancer Center, Graduate School of Cancer Science and Policy, Public Health (2020)
Master of Public Health, National Cancer Center, Graduate School of Cancer Science and Policy, Public Health (2016)
Bachelor of Arts, Emory University, Economics, Theater Studies (2012)
Current Research and Scholarly Interests
My major research interests include cancer epidemiology with a concentration in early detection and screening for cancer. My current research focuses on second malignancies among cancer survivors with special interests in causal inference from real-world observational data sources, dynamic risk predictive modeling, and simulation models of cancer control interventions on their effects on population trends in incidence and mortality. My research involves the application of competing-risk and high-dimensional data analysis using large population-based prospective cohorts, clinical trial data, electronic health records extracted through the data mining process, and cancer genomics data.
Predictive Model to Guide Brain Magnetic Resonance Imaging Surveillance in Patients With Metastatic Lung Cancer: Impact on Real-World Outcomes.
JCO precision oncology
2022; 6: e2200220
Brain metastasis is common in lung cancer, and treatment of brain metastasis can lead to significant morbidity. Although early detection of brain metastasis may improve outcomes, there are no prediction models to identify high-risk patients for brain magnetic resonance imaging (MRI) surveillance. Our goal is to develop a machine learning-based clinicogenomic prediction model to estimate patient-level brain metastasis risk.A penalized regression competing risk model was developed using 330 patients diagnosed with lung cancer between January 2014 and June 2019 and followed through June 2021 at Stanford HealthCare. The main outcome was time from the diagnosis of distant metastatic disease to the development of brain metastasis, death, or censoring.Among the 330 patients, 84 (25%) developed brain metastasis over 627 person-years, with a 1-year cumulative brain metastasis incidence of 10.2% (95% CI, 6.8 to 13.6). Features selected for model inclusion were histology, cancer stage, age at diagnosis, primary site, and RB1 and ALK alterations. The prediction model yielded high discrimination (area under the curve 0.75). When the cohort was stratified by risk using a 1-year risk threshold of > 14.2% (85th percentile), the high-risk group had increased 1-year cumulative incidence of brain metastasis versus the low-risk group (30.8% v 6.1%, P < .01). Of 48 high-risk patients, 24 developed brain metastasis, and of these, 12 patients had brain metastasis detected more than 7 months after last brain MRI. Patients who missed this 7-month window had larger brain metastases (58% v 33% largest diameter > 10 mm; odds ratio, 2.80, CI, 0.51 to 13) versus those who had MRIs more frequently.The proposed model can identify high-risk patients, who may benefit from more intensive brain MRI surveillance to reduce morbidity of subsequent treatment through early detection.
View details for DOI 10.1200/PO.22.00220
View details for PubMedID 36201713
Trends in the Performance of the Korean National Cancer Screening Program for Gastric Cancer from 2007 to 2016
CANCER RESEARCH AND TREATMENT
2022; 54 (3): 842-849
The Korean National Cancer Screening Program (KNCSP) has implemented two screening methods for gastric cancer-upper gastrointestinal series (UGIS) and endoscopy-for Koreans aged ≥40 years. We aimed to assess performance trends for both screening methods.The KNCSP database was used to evaluate individuals who underwent screening from 2007 to 2016. The final gastric cancer diagnosis was ascertained by linking with the Korean Central Cancer Registry. We conducted a prospective, cross-sectional analysis to estimate performance indicators of gastric cancer screening by UGIS and endoscopy, stratified by sociodemographic factors.We found that screening rates for gastric cancer increased from 28% to 51.7% between 2007 and 2016, and that the rate of endoscopy use for gastric cancer screening increased sharply. Cancer detection rates (CDR) of UGIS and endoscopy were 0.41 and 2.25 per 1,000 screens in 2007-2008 and 0.26 and 1.99 in 2015-2016, respectively. Interval cancer rates (ICR) per 1,000 negative screenings were 1.33 (2007-2008) and 1.21 (2015-2016) for UGIS and 1.14 (2007-2008) and 0.88 (2015-2016) for endoscopy. The sensitivity of UGIS decreased from 23.6% (2007-2008) to 17.6% (2015-2016), whereas that of endoscopy increased from 66.4% (2007-2008) to 69.3% (2015-2016). Specificity was maintained at >99% for both methods over the study period.The use of endoscopy for gastric cancer screening within the KNCSP has increased. Endoscopy has higher CDR, sensitivity, and specificity, and lower ICR estimates than does UGIS.
View details for DOI 10.4143/crt.2021.482
View details for Web of Science ID 000853347100021
View details for PubMedID 34607395
View details for PubMedCentralID PMC9296921
Racial and Ethnic Disparities in Lung Cancer Screening by the 2021 USPSTF Guidelines Versus Risk-Based Criteria: The Multiethnic Cohort Study.
JNCI cancer spectrum
2022; 6 (3)
BACKGROUND: In 2021, the US Preventive Services Task Force (USPSTF) revised its lung cancer screening guidelines to expand screening eligibility. We evaluated screening sensitivities and racial and ethnic disparities under the 2021 USPSTF criteria vs alternative risk-based criteria in a racially and ethnically diverse population.METHODS: In the Multiethnic Cohort, we evaluated the proportion of ever-smoking lung cancer cases eligible for screening (ie, screening sensitivity) under the 2021 USPSTF criteria and under risk-based criteria through the PLCOm2012 model (6-year risk≥1.51%). We also calculated the screening disparity (ie, absolute sensitivity difference) for each of 4 racial or ethnic groups (African American, Japanese American, Latino, Native Hawaiian) vs White cases.RESULTS: Among 5900 lung cancer cases, 43.3% were screen eligible under the 2021 USPSTF criteria. Screening sensitivities varied by race and ethnicity, with Native Hawaiian (56.7%) and White (49.6%) cases attaining the highest sensitivities and Latino (37.3%), African American (38.4%), and Japanese American (40.0%) cases attaining the lowest. Latino cases had the greatest screening disparity vs White cases at 12.4%, followed by African American (11.2%) and Japanese American (9.6%) cases. Under risk-based screening, the overall screening sensitivity increased to 75.7%, and all racial and ethnic groups had increased sensitivities (54.5%-91.9%). Whereas the screening disparity decreased to 5.1% for African American cases, it increased to 28.6% for Latino cases and 12.8% for Japanese American cases.CONCLUSIONS: In the Multiethnic Cohort, racial and ethnic disparities decreased but persisted under the 2021 USPSTF lung cancer screening guidelines. Risk-based screening through PLCOm2012 may increase screening sensitivities and help to reduce disparities in some, but not all, racial and ethnic groups. Further optimization of risk-based screening strategies across diverse populations is needed.
View details for DOI 10.1093/jncics/pkac033
View details for PubMedID 35642317
Smoking Cessation After Lung Cancer Diagnosis and the Risk of Second Primary Lung Cancer: The Multiethnic Cohort Study.
JNCI cancer spectrum
2021; 5 (5): pkab076
Background: Smoking cessation reduces lung cancer mortality. However, little is known about whether diagnosis of lung cancer impacts changes in smoking behaviors. Furthermore, the effects of smoking cessation on the risk of second primary lung cancer (SPLC) have not been established yet. This study aims to examine smoking behavior changes after initial primary lung cancer (IPLC) diagnosis and estimate the effect of smoking cessation on SPLC risk following IPLC diagnosis.Methods: The study cohort consisted of 986 participants in the Multiethnic Cohort Study who were free of lung cancer and active smokers at baseline (1993-1996), provided 10-year follow-up smoking data (2003-2008), and were diagnosed with IPLC in 1993-2017. The primary outcome was a change in smoking status from "current" at baseline to "former" at 10-year follow-up (ie, smoking cessation), analyzed using logistic regression. The second outcome was SPLC incidence after smoking cessation, estimated using cause-specific Cox regression. All statistical tests were 2-sided.Results: Among 986 current smokers at baseline, 51.1% reported smoking cessation at 10-year follow-up. The smoking cessation rate was statistically significantly higher (80.6%) for those diagnosed with IPLC between baseline and 10-year follow-up vs those without IPLC diagnosis (45.4%) during the 10-year period (adjusted odds ratio = 5.12, 95% confidence interval [CI] = 3.38 to 7.98; P<.001). Incidence of SPLC was statistically significantly lower among the 504 participants who reported smoking cessation at follow-up compared with those without smoking cessation (adjusted hazard ratio = 0.31, 95% CI = 0.14 to 0.67; P=.003).Conclusion: Lung cancer diagnosis has a statistically significant impact on smoking cessation. Quitting smoking after IPLC diagnosis may reduce the risk of developing a subsequent malignancy in the lungs.
View details for DOI 10.1093/jncics/pkab076
View details for PubMedID 34611582
Development and Validation of a Risk Prediction Tool for Second Primary Lung Cancer.
Journal of the National Cancer Institute
BACKGROUND: With advancing therapeutics, lung cancer (LC) survivors are rapidly increasing in number. While mounting evidence suggests LC survivors have high risk of second primary lung cancer (SPLC), there is no validated prediction tool available for clinical use to identify high-risk LC survivors for SPLC.METHODS: Using data from 6,325 ever-smokers in the Multiethnic Cohort (MEC) diagnosed with initial primary lung cancer (IPLC) in 1993-2017, we developed a prediction model for 10-year SPLC risk after IPLC diagnosis using cause-specific Cox regression. We evaluated the model's clinical utility using decision curve analysis and externally validated it using two population-based data, PLCO and NLST, that included 2,963 and 2,844 IPLC (101 and 93 SPLC cases), respectively.RESULTS: Over 14,063 person-years, 145 (2.3%) developed SPLC in MEC. Our prediction model demonstrated a high predictive accuracy (Brier score = 2.9, 95% confidence interval [CI] = 2.4-3.3) and discrimination (AUC = 81.9%, 95% CI=78.2%-85.5%) based on bootstrap validation in MEC. Stratification by the estimated risk quartiles showed that the observed SPLC incidence was statistically significantly higher in the 4th versus 1st quartile (9.5% versus 0.2%; P<.001). Decision curve analysis indicated that in a wide range of 10-year risk thresholds from 1% to 20%, the model yielded a larger net-benefit versus hypothetical all-screening or no-screening scenarios. External validation using PLCO and NLST showed an AUC of 78.8% (95% CI=74.6%-82.9%) and 72.7% (95% CI=67.7%-77.7%), respectively.CONCLUSIONS: We developed and validated a SPLC prediction model based on large population-based cohorts. The proposed prediction tool can help identify high-risk LC patients for SPLC and can be incorporated into clinical decision-making for SPLC surveillance and screening.
View details for DOI 10.1093/jnci/djab138
View details for PubMedID 34255071
Effectiveness of the Korean National Cancer Screening Program in reducing breast cancer mortality.
NPJ breast cancer
2021; 7 (1): 83
High incidences of breast cancer (BC) are reported in Asian women in their forties, and it is not clear whether mammographic screening reduces mortality among them. This study evaluated the effect of BC screening on mortality in Korea. We conducted a nationwide prospective cohort study of women invited to the Korean National Cancer Screening Program (KNCSP) between 2002 and 2003 (N=8,300,682), with data linkage to the Korea Central Cancer Registry and death certificates through 2014 and 2015, respectively. Exposure to mammographic screening was defined using a modified never/ever approach. The primary study outcome was adjusted mortality rate ratio (MRR) for BC among screened and non-screened women estimated by Poisson regression. An adjusted MRR for all cause-death other than BC was examined to account for selection bias in the cohort. BC incidence rates for screened and non-screened women were 84.41 and 82.88 per 100,000 women-years, respectively. BC mortality rates for screened and non-screened women were 5.81 and 13.43 per 100,000 women-years, respectively, with an adjusted MRR for BC of 0.43 (95% CI, 0.41-0.44). The adjusted MRR for all-cause death excluding BC was 0.52 (95% CI, 0.52-0.52). The greatest reduction in BC mortality was noted for women aged 45-54 years, and there was no observable reduction in mortality after the age of 70 years. In conclusion, the KNCSP has been effective in reducing BC mortality among Korean women aged 40-69 years.
View details for DOI 10.1038/s41523-021-00295-9
View details for PubMedID 34183679
The Survival Impact of Second Primary Lung Cancer in Patients with Lung Cancer.
Journal of the National Cancer Institute
Lung cancer survivors have a high risk of developing second primary lung cancer (SPLC), but little is known about the survival impact of SPLC diagnosis.We analyzed data from 138,969 patients in the Surveillance, Epidemiology, and End Results (SEER), who were surgically treated for initial primary lung cancer (IPLC) in 1988-2013. Each patient was followed from the date of IPLC diagnosis to SPLC diagnosis (for those with SPLC) and last vital status through 2016. We performed multivariable Cox regression to evaluate the association between overall survival and SPLC diagnosis as a time-varying predictor. To investigate potential effect modification, we tested interaction between SPLC and IPLC stage. Using data from the Multiethnic Cohort Study (MEC) (N = 1,540 IPLC patients with surgery), we evaluated the survival impact of SPLC by smoking status. All statistical tests were 2-sided.A total of 12,115 (8.7%) patients developed SPLC in SEER over 700,421 person-years of follow up. Compared to patients with single primary lung cancer, those with SPLC had statistically significantly reduced overall survival (hazard ratio [HR]=2.12, 95% confidence interval [CI] = 2.06-2.17; P < .001). The effect of SPLC on reduced survival was more pronounced among patients with early-stage IPLC vs. advanced-stage IPLC (HR = 2.14 [95% CI = 2.08-2.20] vs. 1.43 [95% CI = 1.21-1.70], respectively; Pinteraction <0.001). Analysis using MEC data showed that the effect of SPLC on reduced survival was statistically significantly larger among persons who actively smoked at initial diagnosis vs. those who formerly or never smoked (HR = 2.31 [95% CI = 1.48-3.61] vs. 1.41 [95% CI = 0.98-2.03], respectively; Pinteraction=0.04).SPLC diagnosis is statistically significantly associated with decreased survival in SEER and MEC. Intensive surveillance targeting patients with early-stage IPLC and active smoking at IPLC diagnosis may lead to a larger survival benefit.
View details for DOI 10.1093/jnci/djab224
View details for PubMedID 34893871
ARS2/MAGL signaling in glioblastoma stem cells promotes self-renewal and M2-like polarization of tumor-associated macrophages
2020; 11 (1): 2978
The interplay between glioblastoma stem cells (GSCs) and tumor-associated macrophages (TAMs) promotes progression of glioblastoma multiforme (GBM). However, the detailed molecular mechanisms underlying the relationship between these two cell types remain unclear. Here, we demonstrate that ARS2 (arsenite-resistance protein 2), a zinc finger protein that is essential for early mammalian development, plays critical roles in GSC maintenance and M2-like TAM polarization. ARS2 directly activates its novel transcriptional target MGLL, encoding monoacylglycerol lipase (MAGL), to regulate the self-renewal and tumorigenicity of GSCs through production of prostaglandin E2 (PGE2), which stimulates β-catenin activation of GSC and M2-like TAM polarization. We identify M2-like signature downregulated by which MAGL-specific inhibitor, JZL184, increased survival rate significantly in the mouse xenograft model by blocking PGE2 production. Taken together, our results suggest that blocking the interplay between GSCs and TAMs by targeting ARS2/MAGL signaling offers a potentially novel therapeutic option for GBM patients.
View details for DOI 10.1038/s41467-020-16789-2
View details for Web of Science ID 000542758700008
View details for PubMedID 32532977
View details for PubMedCentralID PMC7293269
Socioeconomic inequalities in obesity among Korean women aged 19-79 years: the 2016 Korean Study of Women's Health-Related Issues
EPIDEMIOLOGY AND HEALTH
2019; 41: e2019005
While the prevalence of obesity in Asian women has remained stagnant, studies of socioeconomic inequalities in obesity among Asian women are scarce. This study aimed to examine the recent prevalence of obesity in Korean women aged between 19 years and 79 years and to analyze socioeconomic inequalities in obesity.Data were derived from the 2016 Korean Study of Women's Health-Related Issues. The chi-square test and logistic regression analysis were used to analyze the associations between socioeconomic factors and obesity using Asian standard body mass index (BMI) categories: low (<18.5 kg/m2 ), normal (18.5-22.9 kg/m2 ), overweight (23.0-24.9 kg/m2 ), and obese (≥25.0 kg/ m2 ). As inequality-specific indicators, the slope index of inequality (SII) and relative index of inequality (RII) were calculated, with adjustment for age and self-reported health status.Korean women were classified into the following BMI categories: underweight (5.3%), normal weight (59.1%), overweight (21.2%), and obese (14.4%). The SII and RII revealed substantial inequalities in obesity in favor of more urbanized women (SII, 4.5; RII, 1.4) and against of women who were highly educated (SII, -16.7; RII, 0.3). Subgroup analysis revealed inequalities in obesity according to household income among younger women and according to urbanization among women aged 65-79 years.Clear educational inequalities in obesity existed in Korean women. Reverse inequalities in urbanization were also apparent in older women. Developing strategies to address the multiple observed inequalities in obesity among Korean women may prove essential for effectively reducing the burden of this disease.
View details for DOI 10.4178/epih.e2019005
View details for Web of Science ID 000463224900001
View details for PubMedID 30917463
View details for PubMedCentralID PMC6446067
Socioeconomic Inequalities in Cervical and Breast Cancer Screening among Women in Korea, 2005-2015
YONSEI MEDICAL JOURNAL
2018; 59 (9): 1026–33
Consistent evidence indicates that cervical and breast cancer screening rates are low among socioeconomically deprived women. This study aimed to assess trends in cervical and breast cancer screening rates and to analyze socioeconomic inequalities among Korean women from 2005 to 2015.Data from the Korean National Cancer Screening Survey, an annual nationwide cross-sectional survey, were utilized. A total of 19910 women were finally included for analysis. Inequalities in education and household income status were estimated by slope index of inequality (SII) and relative index of inequality (RII), along with calculation of annual percent changes (APCs), to show trends in cancer screening rates.Cervical and breast cancer screening rates increased from 54.8% in 2005 to 65.6% in 2015 and from 37.6% in 2005 to 61.2% in 2015, respectively. APCs in breast cancer screening rates were significant among women with higher levels of household income and education status. Inequalities by household income in cervical cancer screening uptake were observed with a pooled SII estimate of 10.6% (95% CI: 8.1 to 13.2) and RII of 1.4 (95% CI: 1.3 to 1.6). Income inequalities in breast cancer screening were shown to gradually increase over time with a pooled SII of 5.9% (95% CI: 2.9 to 9.0) and RII of 1.2 (95% CI: 0.9 to 1.3). Educational inequalities appeared to diminish over the study period for both cervical and breast cancer screening.Our study identified significant inequalities among socioeconomically deprived women in cervical and breast cancer screening in Korea. Especially, income-related inequalities were greater than education-related inequalities, and these were constant from 2005 to 2015 for both cervical and breast cancer screening.
View details for DOI 10.3349/ymj.2018.59.9.1026
View details for Web of Science ID 000447631100003
View details for PubMedID 30328316
View details for PubMedCentralID PMC6192888
Associations of perceived risk and cancer worry for colorectal cancer with screening behaviour
JOURNAL OF HEALTH PSYCHOLOGY
2018; 23 (6): 840–52
We investigated the associations of perceived risk and cancer worry with colorectal cancer screening by the faecal occult blood test, colonoscopy or both. This study was based on the 2013 Korean National Cancer Screening Survey, including 2154 randomly selected, cancer-free and over 50-year-old adults. Individuals with higher cancer worry were 1.53 times more likely to undergo colorectal cancer screening, influenced by emotional reaction; individuals with greater perceived risk were 1.61 times more, affected by subjective awareness. However, cancer worry was only associated with the faecal occult blood test. Better understanding of cancer worry and perceived risk on screening behaviours may help to increase colorectal cancer screening rates.
View details for DOI 10.1177/1359105316679721
View details for Web of Science ID 000430332700008
View details for PubMedID 27872387
Cancer mortality-to-incidence ratio as an indicator of cancer management outcomes in Organization for Economic Cooperation and Development countries
EPIDEMIOLOGY AND HEALTH
2017; 39: e2017006
Assessing long-term success and efficiency is an essential part of evaluating cancer control programs. The mortality-to-incidence ratio (MIR) can serve as an insightful indicator of cancer management outcomes for individual nations. By calculating MIRs for the top five cancers in Organization for Economic Cooperation and Development (OECD) countries, the current study attempted to characterize the outcomes of national cancer management policies according to the health system ranking of each country.The MIRs for the five most burdensome cancers globally (lung, colorectal, prostate, stomach, and breast) were calculated for all 34 OECD countries using 2012 GLOBOCAN incidence and mortality statistics. Health system rankings reported by the World Health Organization in 2000 were updated with relevant information when possible. A linear regression model was created, using MIRs as the dependent variable and health system rankings as the independent variable.The linear relationships between MIRs and health system rankings for the five cancers were significant, with coefficients of determination ranging from 49 to 75% when outliers were excluded. A clear outlier, Korea reported lower-than-predicted MIRs for stomach and colorectal cancer, reflecting its strong national cancer control policies, especially cancer screening.The MIR was found to be a practical measure for evaluating the long-term success of cancer surveillance and the efficacy of cancer control programs, especially cancer screening. Extending the use of MIRs to evaluate other cancers may also prove useful.
View details for DOI 10.4178/epih.e2017006
View details for Web of Science ID 000439454900006
View details for PubMedID 28171715
View details for PubMedCentralID PMC5434228
Relationship between Cancer Worry and Stages of Adoption for Breast Cancer Screening among Korean Women
2015; 10 (7): e0132351
The possibility of developing breast cancer is a concern for all women; however, few studies have examined the relationship between cancer worry and the stages of adoption for breast cancer screening in Korea. Here, we investigated the associations between cancer worry, the stages of adopting breast cancer screening, and socio-demographic factors known to influence screening behaviors.This study was based on the 2013 Korean National Cancer Screening Survey, an annual cross-sectional survey that utilized nationally representative random sampling to investigate cancer screening rates. Data were analyzed from 1,773 randomly selected women aged 40-74 years. Chi-squared tests and multinomial logistic analyses were conducted to determine the associations between cancer worry and the stages of adoption for breast cancer screening and to outline the factors associated with each stage.Korean women were classified into the following stages of adoption for breast cancer screening: pre-contemplation (24.7%), contemplation (13.0%), action/maintenance (50.8%), relapse risk (8.9%), and relapse (2.6%). Women in the action/maintenance stages reported more moderate to higher levels of worry about getting cancer than those in the pre-contemplation stage. Further, age of 40-49 years and having private cancer insurance were associated with women in the action/maintenance stages.Interventions to address breast cancer worry may play an important role in increasing participation and equity in breast cancer screening.
View details for DOI 10.1371/journal.pone.0132351
View details for Web of Science ID 000358198700039
View details for PubMedID 26186652
View details for PubMedCentralID PMC4506072
Association between social support and postpartum depression.
2022; 12 (1): 3128
Postpartum depression is common; however, little is known about its relationship to social support and postpartum depression. This study examined the association between them among South Korean women within one year of childbirth. This study was based on the 2016 Korean Study of Women's Health-Related Issues (K-Stori), a cross-sectional survey employing nationally-representative random sampling. Participants were 1,654 postpartum women within a year of giving birth. Chi-square test and logistic regression analysis were conducted to analyze the associations between social support (and other covariates) and postpartum depression. Among participants, 266 (16.1%) had postpartum depression. Depending on the level of social support, 6.0%, 53.9%, and 40.1% of them had low, moderate, and high social support, respectively. Women with moderate or low social support were more likely to have postpartum depression (OR=1.78, 95% CI=1.26-2.53; OR=2.76, 95% CI=1.56-4.89). This trend was observed in participants with multiparity, pregnancy loss, obese body image, and employed women. Social support was associated with a decreased likelihood of postpartum depression, indicating the importance of social support, especially for women experiencing multiparity, pregnancy loss, negative body image, as well as for employed women.
View details for DOI 10.1038/s41598-022-07248-7
View details for PubMedID 35210553
- Author Correction: Association between social support and postpartum depression. Scientific reports 2022; 12 (1): 3899
Sleep Quality and Associated Factors in Premenopausal, Perimenopausal, and Postmenopausal Women in Korea: Findings from the K-Stori 2016.
Nature and science of sleep
2021; 13: 1137-1145
Poor sleep quality is a common problem among middle-aged women. Few studies, however, have assessed differences in sleep quality among premenopausal, perimenopausal, and postmenopausal women and related risk factors in Korea women. The aim of this study was to assess sleep quality and factors associated therewith according to menopausal status in Korean women.This study was based on the 2016 Korean Study of Women's Health Related Issues (K-Stori), a cross-sectional survey employing nationally representative random sampling. In total, 3000 Korean women aged 45 to 64 years completed the Pittsburgh Sleep Quality Index (PSQI). Comparison of demographic characteristics and sleep quality among pre-, peri-, and postmenopausal women was conducted.Among the participants, 26% suffered from poor sleep quality based on the PSQI. The prevalence of poor sleep quality increased with later menopausal stage (from 18.8% in the premenopausal stage to 29.5% in the postmenopausal stage P <0.001). Multivariate logistic regression analysis showed that peri- and postmenopausal women were 1.50 and 1.73 times more likely to have poor sleep quality in comparison to premenopausal women, respectively. Chronic disease, depression, at-risk drinking, taking dietary supplements, and single women were associated with a higher likelihood of having poor sleep quality. Health status, at-risk drinking, chronic illness, dietary supplementation, and depression were significantly associated with poor sleep quality.Poor sleep quality appears to be prevalent in peri- and postmenopausal women in Korea. The management of sleep quality during menopause transition is important, and further research on how sleep disturbances influence the health status of women in menopausal transition is required.
View details for DOI 10.2147/NSS.S298397
View details for PubMedID 34285618
View details for PubMedCentralID PMC8286781
Tobacco Smoking and Risk of Second Primary Lung Cancer.
Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer
Lung cancer survivors are at high risk of a second primary lung cancer (SPLC). However, SPLC risk factors have not been established and the impact of tobacco smoking remains controversial. We examined risk factors for SPLC across multiple epidemiologic cohorts and assessed the impact of smoking cessation on reducing SPLC risk.We analyzed data from 7,059 participants in the Multiethnic Cohort (MEC) diagnosed with an initial primary lung cancer (IPLC) between 1993 and 2017. Cause-specific proportional hazards models estimated SPLC risk. We conducted validation studies using the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO, N=3,423 IPLC cases) and European Prospective Investigation into Cancer and Nutrition (EPIC, N=4,731 IPLC cases) cohorts and pooled the SPLC risk estimates using random effects meta-analysis.Overall, 163 (2.3%) MEC cases developed a SPLC. Smoking pack-years (HR 1.18 per 10 pack-years; P<0.001) and smoking intensity (HR 1.30 per 10 cigarettes per day (CPD); P<0.001) were significantly associated with increased SPLC risk. Individuals who met the 2013 U.S. Preventive Services Task Force's (USPSTF) screening criteria at IPLC diagnosis also had an increased SPLC risk (HR 1.92; P<0.001). Validation studies with PLCO and EPIC showed consistent results. Meta-analysis yielded pooled HRs of 1.16 per 10 pack-years (Pmeta<0.001), 1.25 per 10 CPD (Pmeta<0.001), and 1.99 (Pmeta<0.001) for meeting the USPSTF criteria. In MEC, smoking cessation after IPLC diagnosis was associated with an 83% reduction in SPLC risk (HR 0.17; P<0.001).Tobacco smoking is a risk factor for SPLC. Smoking cessation after IPLC diagnosis may reduce the risk of SPLC. Additional strategies for SPLC surveillance and screening are warranted.
View details for DOI 10.1016/j.jtho.2021.02.024
View details for PubMedID 33722709
Trend analysis of process quality indicators for the Korean National Cervical Cancer Screening Program from 2005 to 2013
JOURNAL OF GYNECOLOGIC ONCOLOGY
2021; 32 (1): e14
This study sought to examine changes in trends for quality indicators of the population-based Korean National Cancer Screening Program (KNCSP) for cervical cancer from years 2005 to 2013.Our study data were derived from the KNCSP database. Cervical cancer diagnosis information was ascertained through linkage with the Korean National Cancer Registry and the KNCSP database. Performance measures for cervical cancer screening were estimated, including participation rate, positive rate, crude detection rate (CDR), interval cancer rate (ICR), positive predictive value (PPV), sensitivity, and specificity. Joinpoint analysis was applied to calculate annual percentage changes (APCs) in all indicators according to socio-demographic factors.A significant increasing trend was noted in participation rates (APC=13.4%; 95% confidence interval [CI]=10.5, 16.4). PPV and specificity increased from years 2005 to 2009 and remained stable till 2013. An increasing trend was discovered in CDRs for cervical cancer in situ (APC=3.9%; 95% CI=1.0, 6.9), whereas a decreasing trend was observed in ICRs for invasive cervical cancer (APC=-2.5%; 95% CI=-4.5, -0.5). Medical Aid recipients and women older than 70 years showed the lowest participation rates, but higher CDRs and ICRs, compared to other groups. In general, most of the quality indicators for cervical cancer screening improved from 2005 to 2009 and remained stable to 2013.The KNCSP for cervical cancer in Korea has improved in terms of participation rate and accuracy of the screening test. These results may be attributed to the National Quality Improvement Program for KNCSP.
View details for DOI 10.3802/jgo.2021.32.e14
View details for Web of Science ID 000601383100012
View details for PubMedID 33327046
View details for PubMedCentralID PMC7767658
Weight control behaviors according to body weight status and accuracy of weight perceptions among Korean women: a nationwide population-based survey
2019; 9: 9127
This study aimed to identify associations among self-perceived weight status, accuracy of weight perceptions, and weight control behaviors, including both healthy and unhealthy behaviors, in a large, nationally representative sample from an East Asian country. Data were collected from the 2016 Korean Study of Women's Health Related Issues, a population-based, nationwide survey. Accurate weight perceptions were investigated by comparing body mass index (BMI) categories, based on self-reported height and weight, and weight perceptions. Weight control behaviors over the previous 12 months were additionally surveyed. Odds ratios (ORs) and 95% confidence intervals (CIs) are presented as an index of associations. Among normal weight, overweight, and obese women, 12.8%, 44.3%, and 17.4% under-assessed their weight; 17.9% of normal weight women over-assessed their weight. Both weight status according to BMI category and weight perceptions were strongly associated with having tried to lose weight. Exercise and diet (ate less) were the most commonly applied weight control behaviors. Misperception of weight was related to more unhealthy weight control behaviors and less healthy behaviors: Women who under-assessed their weight showed a lower tendency to engage in dieting (OR = 0.57, 95% CI = 0.43-0.75) and a greater tendency to fast/skip meals (OR = 1.47, 95% CI = 1.07-1.99). Meanwhile, normal weight or overweight women who over-assessed their weight were more likely to have engaged in fasting/skipping meals or using diet pills (OR = 5.72, 95% CI = 2.45-13.56 for fasting/skipping meal in overweight women; OR = 1.62, 95% CI = 1.15-2.29 and OR = 3.16, 95% CI = 1.15-8.23 for using diet pills in normal and overweight women). Inaccuracy of weight perceptions in any direction (over/under) were related to more unhealthy weight control behaviors and less healthy weight control behaviors, especially in normal and overweight women.
View details for DOI 10.1038/s41598-019-45596-z
View details for Web of Science ID 000472597400030
View details for PubMedID 31235742
View details for PubMedCentralID PMC6591250
Determinants of undergoing thyroid cancer screening in Korean women: a cross-sectional analysis from the K-Stori 2016
2019; 9 (4): e026366
Thyroid cancer is the most common cancer among Korean women. Studies suggest that the incidence of thyroid cancer might be associated with overdiagnosis resulting from thyroid cancer screening. The objective of this study was to identify the determinants of participation in thyroid cancer screening in Korean women.Data were obtained from the 2016 Korean Study of Women's Health-Related Issues, a nationwide cross-sectional survey of women according to the reproductive life cycle. A total of 8697 cancer-free women of ages between 20 and 79 years were included for analysis. Multivariable logistic regression analysis was applied to analyse factors associated with adherence to thyroid cancer screening based on Andersen's health behavioural model.Over the last 2 years, the rate of thyroid cancer screening was 39.2%. In multivariable models, older age, higher household income, high school education level and higher perceived risk of cancer were positively associated with thyroid cancer screening participation. Moreover, women who underwent cervical cancer screening (adjusted OR [aOR] 3.67; 95% CI 2.90 to 4.64) and breast cancer screening (aOR 10.91; 95% CI 8.41 to 14.14) had higher odds of attending thyroid cancer screening than women who did not attend cancer screening.These findings highlight the need to increase awareness of different recommendations on screening for various cancers to improve cost-effectiveness and to prevent unnecessary treatments.
View details for DOI 10.1136/bmjopen-2018-026366
View details for Web of Science ID 000471157200180
View details for PubMedID 30948602
View details for PubMedCentralID PMC6500224
Self-perceptions of body weight status according to age-groups among Korean women: A nationwide population-based survey
2019; 14 (1): e0210486
While numerous studies have investigated body image, including body weight perception, most of which have focused on adolescents or young women, few studies have attempted to evaluate body weight perceptions in adult women according to age groups. This study was conducted to investigate the accuracy of self-perceived weight and actual body mass index (BMI) values among adult Korean women according to age. We used data from the 2016 Korean Study of Women's Health Related Issues, a population-based, nationwide, cross-sectional survey. BMI was calculated from self-reported weight and height. Participants were asked to describe their body image by choosing one of the following descriptions: very underweight, underweight, about right, overweight, or obese. The proportions of women aged 20-29, 30-39, 40-49, 50-59, 60-69, and 70-79 years who underestimated their body weight relative to their actual BMI category were 12.6%, 15.1%, 22.2%, 34.0%, 45.6%, and 50.7%, respectively; those who overestimated their body weight comprised 18.7%, 17.8%, 14.3%, 10.8%, and 7.4%. In all BMI categories, the proportion of those who overestimated their weight status increased as age decreased, while those who underestimated their weight status increased as age increased. After adjusting for possible covariates, age was strongly associated with both underestimation and overestimation. The odds ratio for underestimating one's weight status among women aged 70-79 yeas was 2.96 (95% CI: 2.10-4.18), and that for overestimation was 0.52 (95% CI: 0.35-0.79), compared to women aged 20-29 years. Age is the most important factor associated with weight perceptions among Korean women, affecting both underestimation and overestimation of weight status.
View details for DOI 10.1371/journal.pone.0210486
View details for Web of Science ID 000456015500042
View details for PubMedID 30653596
View details for PubMedCentralID PMC6336301
Socioeconomic Inequalities in Colorectal Cancer Screening in Korea, 2005-2015: After the Introduction of the National Cancer Screening Program
YONSEI MEDICAL JOURNAL
2018; 59 (9): 1034–40
This study aimed to investigate inequalities in colorectal cancer (CRC) screening rates in Korea and trends therein using the slope index of inequality (SII) and relative index of inequality (RII) across income and education groups.Data from the Korean National Cancer Screening Survey, an annually conducted, nationwide cross-sectional survey, were utilized. A total of 17174 men and women aged 50 to 74 years were included for analysis. Prior experience with CRC screening was defined as having either a fecal occult blood test within the past year or a lifetime colonoscopy. CRC screening rates and annual percentage changes (APCs) were evaluated. Then, SII and RII were calculated to assess inequality in CRC screening for each survey year.CRC screening rates increased from 23.4% in 2005 to 50.9% in 2015 (APC, 7.8%; 95% CI, 6.0 to 9.6). Upward trends in CRC screening rates were observed for all age, education, and household income groups. Education inequalities were noted in 2009, 2014, and overall pooled estimates in both indices. Income inequalities were inconsistent among survey years, and overall estimates did not reach statistical significance.Education inequalities in CRC screening among men and women aged 50 to 74 years were observed in Korea. No apparent pattern, however, was found for income inequalities. Further studies are needed to thoroughly outline socio-economic inequalities in CRC screening.
View details for DOI 10.3349/ymj.2018.59.9.1034
View details for Web of Science ID 000447631100004
View details for PubMedID 30328317
View details for PubMedCentralID PMC6192887
Socioeconomic Inequalities in Stomach Cancer Screening in Korea, 2005-2015: After the Introduction of the National Cancer Screening Program
YONSEI MEDICAL JOURNAL
2018; 59 (8): 923–29
This study aimed to investigate socioeconomic inequalities in stomach cancer screening in Korea and trends therein across income and education groups.Data from the Korean National Cancer Screening Survey, a nationwide cross-sectional survey, were utilized. A total of 28913 men and women aged 40 to 74 years were included for analysis. Prior experience with stomach cancer screening was defined as having undergone either an endoscopy or gastrointestinal series within the past two years. The slope index of inequality (SII) and relative index of inequality (RII) were evaluated to check inequalities.Stomach cancer screening rates increased from 40.0% in 2005 to 74.8% in 2015, with an annual percent change of 5.8% [95% confidence interval (CI) 4.2 to 7.5]. Increases in stomach cancer screening rates were observed for all age, education, and household income groups. Inequalities in stomach cancer screening were noted among individuals of differing levels of education, with a pooled SII estimate of 6.14% (95% CI, 3.94 to 8.34) and RII of 1.26 (95% CI, 1.12 to 1.40). Also, income-related inequalities were observed with an SII of 6.93% (95% CI, 4.89 to 8.97) and RII of 1.30 (95% CI, 1.17 to 1.43). The magnitude of inequality was larger for income than for education.Both education and income-related inequalities were found in stomach cancer screening, despite a continuous increase in screening rate over the study period. Income-related inequality was greater than education-related inequality, and this was more apparent in women than in men.
View details for DOI 10.3349/ymj.2018.59.8.923
View details for Web of Science ID 000443831900003
View details for PubMedID 30187698
View details for PubMedCentralID PMC6127424
Inhibition of BMP signaling overcomes acquired resistance to cetuximab in oral squamous cell carcinomas
2018; 414: 181–89
Despite expressing high levels of the epidermal growth factor receptor (EGFR), a majority of oral squamous cell carcinoma (OSCC) patients show limited response to cetuximab and ultimately develop drug resistance. However, mechanism underlying cetuximab resistance in OSCC is not clearly understood. Here, using a mouse orthotopic xenograft model of OSCC, we show that bone morphogenic protein-7-phosphorylated Smad-1, -5, -8 (BMP7-p-Smad1/5/8) signaling contributes to cetuximab resistance. Tumor cells isolated from the recurrent cetuximab-resistant xenograft models exhibited low EGFR expression but extremely high levels of p-Smad1/5/8. Treatment with the bone morphogenic protein receptor type 1 (BMPRI) inhibitor, DMH1 significantly reduced cetuximab-resistant OSCC tumor growth, and combined treatment of DMH1 and cetuximab remarkably reduced relapsed tumor growth in vivo. Importantly, p-Smad1/5/8 level was elevated in cetuximab-resistant patients and this correlated with poor prognosis. Collectively, our results indicate that the BMP7-p-Smad1/5/8 signaling is a key pathway to acquired cetuximab resistance, and demonstrate that combination therapy of cetuximab and a BMP signaling inhibitor as potentially a new therapeutic strategy for overcoming acquired resistance to cetuximab in OSCC.
View details for DOI 10.1016/j.canlet.2017.11.013
View details for Web of Science ID 000419810900019
View details for PubMedID 29154973
Transglutaminase 2 Inhibition Reverses Mesenchymal Transdifferentiation of Glioma Stem Cells by Regulating C/EBP beta Signaling
2017; 77 (18): 4973–84
Necrosis is a hallmark of glioblastoma (GBM) and is responsible for poor prognosis and resistance to conventional therapies. However, the molecular mechanisms underlying necrotic microenvironment-induced malignancy of GBM have not been elucidated. Here, we report that transglutaminase 2 (TGM2) is upregulated in the perinecrotic region of GBM and triggered mesenchymal (MES) transdifferentiation of glioma stem cells (GSC) by regulating master transcription factors (TF), such as C/EBPβ, TAZ, and STAT3. TGM2 expression was induced by macrophages/microglia-derived cytokines via NF-κB activation and further degraded DNA damage-inducible transcript 3 (GADD153) to induce C/EBPβ expression, resulting in expression of the MES transcriptome. Downregulation of TGM2 decreased sphere-forming ability, tumor size, and radioresistance and survival in a xenograft mouse model through a loss of the MES signature. A TGM2-specific inhibitor GK921 blocked MES transdifferentiation and showed significant therapeutic efficacy in mouse models of GSC. Moreover, TGM2 expression was significantly increased in recurrent MES patients and inversely correlated with patient prognosis. Collectively, our results indicate that TGM2 is a key molecular switch of necrosis-induced MES transdifferentiation and an important therapeutic target for MES GBM. Cancer Res; 77(18); 4973-84. ©2017 AACR.
View details for DOI 10.1158/0008-5472.CAN-17-0388
View details for Web of Science ID 000410945700021
View details for PubMedID 28754668
Trends in Participation Rates for the National Cancer Screening Program in Korea, 2002-2012
CANCER RESEARCH AND TREATMENT
2017; 49 (3): 798–806
The National Cancer Screening Program (NCSP) in Korea supports cancer screening for stomach, liver, colorectal, breast, and cervical cancer. This study was conducted to assess trends in participation rates among Korean men and women invited to undergo screening via the NCSP as part of an effort to guide future implementation of the program in Korea.Data from the NCSP for 2002 to 2012 were used to calculate annual participation rates with 95% confidence intervals (CI) by sex, insurance status, and age group for stomach, liver, colorectal, breast, and cervical cancer screening.In 2012, participation rates for stomach, liver, colorectal, breast, and cervical cancer screening were 47.3%, 25.0%, 39.5%, 51.9%, and 40.9%, respectively. The participation rates increased annually by 4.3% (95% CI, 4.0 to 4.6) for stomach cancer, 3.3% (95% CI, 2.5 to 4.1) for liver cancer, 4.1% (95% CI, 3.2 to 5.0) for colorectal cancer, 4.6% (95% CI, 4.1 to 5.0) for breast cancer, and 0.9% (95% CI, -0.7 to 2.5) for cervical cancer from 2002 to 2012.Participant rates for the NCSP for the five above-mentioned cancers increased annually from 2002 to 2012.
View details for DOI 10.4143/crt.2016.186
View details for Web of Science ID 000405537800025
View details for PubMedID 27857022
View details for PubMedCentralID PMC5512374
The Korean Study of Women's Health-Related Issues (K-Stori): Rationale and Study Design
BMC PUBLIC HEALTH
2017; 17: 609
Measures to address gender-specific health issues are essential due to fundamental, biological differences between the sexes. Studies have increasingly stressed the importance of customizing approaches directed at women's health issues according to stages in the female life cycle. In Korea, however, gender-specific studies on issues affecting Korean women in relation to stages in their life cycle are lacking. Accordingly, the Korean Study of Women's Health-Related Issues (K-Stori) was designed to investigate life cycle-specific health issues among women, covering health status, awareness, and risk perceptions.K-Stori was conducted as a nationwide cross-sectional survey targeting Korean women aged 14-79 years. Per each stage in the female life cycle (adolescence, childbearing age, pregnancy & postpartum, menopause, and older adult stage), 3000 women (total 15,000) were recruited by stratified multistage random sampling for geographic area based on the 2010 Resident Registration Population in Korea. Specialized questionnaires per each stage (total of five) were developed in consultation with multidisciplinary experts and by reflecting upon current interests into health among the general population of women in Korea. This survey was conducted from April 1 to June 31, 2016, at which time investigators from a professional research agency went door-to-door to recruit residents and conducted in-person interviews.The study's findings may help with elucidating health issues and unmet needs specific to each stage in the life cycle of Korean women that have yet to be identified in present surveys.
View details for DOI 10.1186/s12889-017-4531-1
View details for Web of Science ID 000405870800006
View details for PubMedID 28662652
View details for PubMedCentralID PMC5492879
Responses to Overdiagnosis in Thyroid Cancer Screening among Korean Women
CANCER RESEARCH AND TREATMENT
2016; 48 (3): 883–91
Communicating the harms and benefits of thyroid screening is necessary to help individuals decide on whether or not to undergo thyroid cancer screening. This study was conducted to assess changes in thyroid cancer screening intention in response to receiving information about overdiagnosis and to determine factors with the greatest influence thereon.Data were acquired from subjects included in the 2013 Korean National Cancer Screening Survey (KNCSS), a nationwide, population-based, cross-sectional survey. Of the 4,100 respondents in the 2013 KNCSS, women were randomly subsampled and an additional face-to-face interview was conducted. Finally, a total of 586 female subjects were included in this study. Intention to undergo thyroid cancer screening was assessed before and after receiving information on overdiagnosis.Prior awareness of overdiagnosis in thyroid cancer screening was 27.8%. The majority of subjects intended to undergo thyroid cancer screening before and after receiving information on overdiagnosis (87% and 74%, respectively). Only a small number of subjects changed their intention to undergo thyroid cancer screening from positive to negative after receiving information on overdiagnosis. Women of higher education level and Medical Aid Program recipients reported being significantly more likely to change their intention to undergo thyroid cancer screening afterreceiving information on overdiagnosis,whilewomen with stronger beliefs on the efficacy of cancer screening were less likely to change their intention.Women in Korea appeared to be less concerned about overdiagnosis when deciding whether or not to undergo thyroid cancer screening.
View details for DOI 10.4143/crt.2015.218
View details for Web of Science ID 000380496900002
View details for PubMedID 26727718
View details for PubMedCentralID PMC4946348
A qualitative study of women's views on overdiagnosis and screening for thyroid cancer in Korea
2015; 15: 858
The incidence of thyroid cancer in Korea has increased by about 25 % every year for the past 10 years. This increase is largely due to a rising incidence in papillary thyroid cancer, which is associated with an overdiagnosis of small tumors that may never become clinically significant. This study was conducted to explore Korean women's understanding of overdiagnosis and to investigate changes in screening intention in response to overdiagnosis information.Focus group interviews were conducted among women of ages 30-69 years, who are commonly targeted in Korea for cancer screening. Women were divided into four groups according to thyroid cancer screening history and history of thyroid disease. Of 51 women who were contacted, 29 (57 %) participated in the interviews.Prior awareness of thyroid cancer overdiagnosis was minimal. When informed about the risks of overdiagnosis, the participants were often surprised. Overcoming initial malcontent, many women remained skeptic about overdiagnosis and trusted in the advice of their physicians. Meanwhile, some of the study participants found explanations of overdiagnosis difficult to understand. Further, hearing about the risks of overdiagnosis had limited impact on the participants' attitudes and intentions to undergo thyroid cancer screening, as many women expressed willingness to undergoing continued screening in the future.A large majority of Korean women eligible for and had undergone thyroid cancer screening were unaware of the potential for overdiagnosis. Nevertheless, overdiagnosis information generally had little impact on their beliefs about thyroid cancer screening and their intentions to undergo future screening. Further research is needed to determine whether these findings could be generalized to the wider Korean population.
View details for DOI 10.1186/s12885-015-1877-6
View details for Web of Science ID 000365267500003
View details for PubMedID 26546276
View details for PubMedCentralID PMC4635590