• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.28 no.2
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• pp.229-237
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• 2024

Backgrounds/Aims: While patients with borderline resectable pancreatic cancer (BRPC) are a target population for neoadjuvant chemotherapy (NAC), formal guidelines for neoadjuvant therapy are lacking. We assessed the perioperative and oncological outcomes in patients with BRPC undergoing NAC with FOLFIRINOX for patients undergoing upfront surgery (US). Methods: The AHPBA criteria for borderline resectability and/or a CA19-9 level > 100 µ/mL defined borderline resectable tumors retrieved from a prospectively populated institutional registry from 2007 to 2020. The primary outcome was overall survival (OS) at 1 and 3 years. A Cox Proportional Hazard model based on intention to treat was used. A receiver-operator characteristics (ROC) curve was constructed to assess the discriminatory capability of the use of CA19-9 > 100 µ/mL to predict resectability and mortality. Results: Forty BRPC patients underwent NAC, while 46 underwent US. The median OS with NAC was 19.8 months (interquartile range [IQR], 10.3-44.24) vs. 10.6 months (IQR, 6.37-17.6) with US. At 1 year, 70% of the NAC group and 41.3% of the US group survived (p = 0.008). At 3 years, 42.5 % of the NAC group and 10.9% of the US group survived (p = 0.001). NAC significantly reduced the hazard of death (adjusted hazard ratio, 0.20; 95% confidence interval, 0.07-0.54; p = 0.001). CA19-9 > 100 µ/mL showed poor discrimination in predicting mortality, but was a moderate predictor of resectability. Conclusions: We found a survival benefit of NAC with FOLFIRINOX for BRPC. Greater pre-treatment of CA19-9 and multivessel involvement on initial imaging were associated with progression of the disease following NAC.

• Annals of Occupational and Environmental Medicine
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• v.34
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• pp.24.1-24.13
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• 2022

Background: In modern society, depression is serious issue that causes socioeconomic and family burden. To decrease the incidence of depression, risk factors should be identified and managed. Among many risk factors for depression, this study examined socioeconomic risk factors for depression. Methods: We utilized first (2006), second (2008), and third (2010)-wave data from the Korean Longitudinal Study of Aging (KLoSA). Depressive symptom was measured with the 10-item Center for Epidemiological Studies Depression Scale, Short Form (CES-D-10) in the survey in 2008 and 2010. Three risk factors including job security, employment type and monthly income were measured in the survey in 2006. The association between risk factors and depressive symptom was analyzed by Cox proportional-hazard model. Results: We analyzed data from 1,105 workers and hazard ratios (HRs) for 3 risk factors were significant entirely. In addition, regular worker with high income group is the most vulnerable group of poor job insecurity on depression among male workers (HR: 1.73; 95% confidence interval [CI]: 1.07-2.81). Finally, HRs for 7 groups who had at least 1 risk factor had higher HRs compared to groups who had no risk factors after stratifying 3 risk factors. In the analysis, significantly vulnerable groups were total 5 groups and the group who had highest HR was temporary/daily workers with poor job security (HR: 2.51; 95% CI: 1.36-4.64). The results concerning women, regardless of job type, were non-significant. Conclusions: This study presented one or more risk factors among poor job security, low income, temporary/daily employment type increase hazard for depressive symptom in 2 or 4 years after the exposure. These results inform policy to screen for and protect against the risk of depression in vulnerable groups.

• Proceedings of the Korean Statistical Society Conference
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• 2005.05a
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• pp.17-23
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• 2005

In this paper we consider the well-known semiparametric proportional hazards models for survival analysis. These models are usually used with few covariates and many observations (subjects). But, for a typical setting of gene expression data from DNA microarray, we need to consider the case where the number of covariates p exceeds the number of samples n. For a given vector of response values which are times to event (death or censored times) and p gene expressions(covariates), we address the issue of how to reduce the dimension by selecting the significant genes. This approach enables us to estimate the survival curve when n ${\ll}$p. In our approach, rather than fixing the number of selected genes, we will assign a prior distribution to this number. The approach creates additional flexibility by allowing the imposition of constraints, such as bounding the dimension via a prior, which in effect works as a penalty To implement our methodology, we use a Markov Chain Monte Carlo (MCMC) method. We demonstrate the use of the methodology to diffuse large B-cell lymphoma (DLBCL) complementary DNA (cDNA) data and Breast Carcinomas data.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5767-5772
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• 2012

Introduction: Identification of simple and measurable prognostic factors is an important issue in treatment evaluation of breast cancer. The present study was conducted to evaluate the prognostic role of vascular invasion in lymph node negative breast cancer patients. Methods: in a retrospective design, we analyzed the recorded profiles of the 1,640 patients treated in the breast cancer department of Motahari clinic affiliated to Shiraz University of Medical Sciences, Shiraz, Iran, from January 1999 to December 2012. Overall and adjusted survivals were evaluated by the Cox proportional hazard model. All the hypotheses were considered two-sided and a p-value of 0.05 or less was considered as statistically significant. Results: Mean age in lymph node negative and positive patients was 50.0 and 49.8 respectively. In lymph node negative patients, the number of nodes, tumor size, lymphatic invasion, vascular invasion, progesterone receptor, and nuclear grade were significant predictors. In lymph node and lymphatic negative patients, vascular invasion also played a significant prognostic role in the survival which was not evident in lymph node negative patients with lymphatic invasion. Discussion: The results of our large cohort study, with long term follow up and using multivariate Cox proportional model and comparative design showed a significant prognostic role of vascular invasion in early breast cancer patients. Vascular invasion as an independent prognostic factor in lymph node negative invasive breast cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6029-6033
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• 2014

The burden and severity of a cancer can be reflected by patterns of survival. Breast cancer prognosis between two countries with a different socioeconomic status and cultural beliefs may exhibit wide variation. This study aimed to describe survival in patients with breast cancer in China and Thailand in relation to demographic and clinical prognostic information. Materials and Methods: We compared the survival of 1,504 Chinese women in Yunnan province and 929 Thai women in Songkhla with breast cancer from 2006 to 2010. Descriptive prognostic comparisons between the Chinese and Thai women were performed by relative survival analysis. A Cox regression model was used to calculate the hazard ratios of death, taking into account the age, disease stage, period of diagnosis and country. Results: The overall 5-year survival proportion for patients diagnosed with breast cancer for Yunnan province (0.72) appeared slightly better than Songkhla (0.70) without statistical significance. Thai women diagnosed with distant and regional breast cancer had poorer survival than Chinese women. Disease stage was the most important determinant of survival from the results of Cox regression model. Conclusions: Breast cancer patients in Kunming had slightly greater five-year survival rate than patients in Songkhla. Both Chinese and Thai women need improvement in prognosis, which could conceivably be attained through increased public education and awareness regarding early detection and compliance to treatment protocols.

• Journal of Preventive Medicine and Public Health
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• v.48 no.4
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• pp.216-224
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• 2015

Objectives: Decreased fertility and impaired health owing to early menopause are significant health issues. Smoking is a modifiable health-related behavior that influences menopausal age. We investigated the effects of smoking-associated characteristics on menopausal age in Korean women. Methods: This study used data from the Korea National Health and Nutrition Examination Survey from 2007 to 2012. Menopausal age in relation to smoking was analyzed as a Kaplan-Meier survival curve for 11 510 women (aged 30 to 65 years). The risk of entering menopause and experiencing early menopause (before age 48) related to smoking were assessed using a Cox proportional hazards model. Results: The menopausal age among smokers was 0.75 years lower than that among non-smokers (p<0.001). The results of the Cox proportional hazards model showed pre-correction and post-correction risk ratios for entering menopause related to smoking of 1.26 (95% confidence interval [CI], 1.09 to 1.46) and 1.27 (95% CI, 1.10 to 1.47), respectively, and pre-correction and post-correction risk ratios for experiencing early menopause related to smoking of 1.36 (95% CI, 1.03 to 1.80) and 1.40 (95% CI, 1.05 to 1.85), respectively. Conclusions: Smokers reached menopause earlier than non-smokers, and their risk for experiencing early menopause was higher.

• Journal of Periodontal and Implant Science
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• v.53 no.3
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• pp.184-193
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• 2023

Purpose: The present study was designed to compare the incidence of periodontitis according to menopausal status and to investigate the possible effect of hormone replacement therapy (HRT) on periodontitis in postmenopausal women using a common data model (CDM) at a single institution. Methods: This study involved retrospective cohort data of 950,751 patients from a 20-year database (2001 to 2020) of Ewha Womans University Mokdong Hospital converted to the Observational Medical Outcomes Partnership CDM. One-way analysis of variance models and the χ² test were used to analyze the statistical differences in patient characteristics among groups. A time-dependent Cox regression analysis was used to calculate hazard ratios and 95% confidence intervals, and P values less than 0.05 were considered to indicate statistical significance. Results: Of the 29,729 patients, 1,307 patients were diagnosed with periodontitis and 28,422 patients were not. Periodontitis was significantly more common among postmenopausal patients regardless of HRT status than among the non-menopausal group (P<0.05). Time-dependent Cox regression analysis showed that the postmenopausal patients had a significantly higher chance of having periodontitis than non-menopausal patients (P<0.05), but after adjustment for age, body mass index, and smoking status, the difference between the non-menopausal and post-menopausal HRT-treated groups was insignificant (P=0.140). Conclusions: Postmenopausal women had a significantly greater risk of periodontitis than non-menopausal women. Additionally, the use of HRT in postmenopausal women could reduce the incidence of periodontitis.

• Journal of Gastric Cancer
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• v.14 no.4
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• pp.259-265
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• 2014

Purpose: Survival analysis of gastric cancer patients requires knowledge about factors that affect survival time. This paper attempted to analyze the survival of patients with incomplete registered data by using imputation methods. Materials and Methods: Three missing data imputation methods, including regression, expectation maximization algorithm, and multiple imputation (MI) using Monte Carlo Markov Chain methods, were applied to the data of cancer patients referred to the cancer institute at Imam Khomeini Hospital in Tehran in 2003 to 2008. The data included demographic variables, survival times, and censored variable of 471 patients with gastric cancer. After using imputation methods to account for missing covariate data, the data were analyzed using a Cox regression model and the results were compared. Results: The mean patient survival time after diagnosis was $49.1{\pm}4.4$ months. In the complete case analysis, which used information from 100 of the 471 patients, very wide and uninformative confidence intervals were obtained for the chemotherapy and surgery hazard ratios (HRs). However, after imputation, the maximum confidence interval widths for the chemotherapy and surgery HRs were 8.470 and 0.806, respectively. The minimum width corresponded with MI. Furthermore, the minimum Bayesian and Akaike information criteria values correlated with MI (-821.236 and -827.866, respectively). Conclusions: Missing value imputation increased the estimate precision and accuracy. In addition, MI yielded better results when compared with the expectation maximization algorithm and regression simple imputation methods.

• Journal of Korean Neurosurgical Society
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• v.64 no.1
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• pp.51-59
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• 2021

Objective : Several studies have reported inconsistent findings among countries on whether off-hour hospital presentation is associated with worse outcome in patients with acute stroke. However, its association is yet not clear and has not been thoroughly studied in Korea. We assessed nationwide administrative data to verify off-hour effect in different subtypes of acute stroke in Korea. Methods : We respectively analyzed the nationwide administrative data of National Emergency Department Information System in Korea; 7144 of ischemic stroke (IS), 2424 of intracerebral hemorrhage (ICH), and 1482 of subarachnoid hemorrhage (SAH), respectively. "Off-hour hospital presentation" was defined as weekends, holidays, and any times except 8:00 AM to 6:00 PM on weekdays. The primary outcome measure was in-hospital mortality in different subtypes of acute stroke. We adjusted for covariates to influence the primary outcome using binary logistic regression model and Cox's proportional hazard model. Results : In subjects with IS, off-hour hospital presentation was associated with unfavorable outcome (24.6% off hours vs. 20.9% working hours, p<0.001) and in-hospital mortality (5.3% off hours vs. 3.9% working hours, p=0.004), even after adjustment for compounding variables (hazard ratio [HR], 1.244; 95% confidence interval [CI], 1.106-1.400; HR, 1.402; 95% CI, 1.124-1.747, respectively). Off-hours had significantly more elderly ≥65 years (35.4% off hours vs. 32.1% working hours, p=0.029) and significantly more frequent intensive care unit admission (32.5% off hours vs. 29.9% working hours, p=0.017) than working hours. However, off-hour hospital presentation was not related to poor short-term outcome in subjects with ICH and SAH. Conclusion : This study indicates that off-hour hospital presentation may lead to poor short-term morbidity and mortality in patients with IS, but not in patients with ICH and SAH in Korea. Excessive death seems to be ascribed to old age or the higher severity of medical conditions apart from that of stroke during off hours.

• Journal of Gastric Cancer
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• v.23 no.4
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• pp.584-597
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• 2023

Purpose: This study aimed to investigate the impact of different types of complications on long-term survival following total gastrectomy for gastric cancer. Materials and Methods: A total of 926 patients who underwent total gastrectomy between 2008 and 2016 were included. Patients were divided into the morbidity and no-morbidity groups, and long-term survival was compared between the 2 groups. The prognostic impact of postoperative morbidity was assessed using a multivariate Cox proportional hazard model, which accounted for other prognostic factors. In the multivariate model, the effects of each complication on survival were analyzed. Results: A total of 229 patients (24.7%) developed postoperative complications. Patients with postoperative morbidity showed significantly worse overall survival (OS) (5-year, 65.0% vs. 76.7%, P<0.001) and cancer-specific survival (CSS) (5-year, 74.2% vs. 83.1%, P=0.002) compared to those without morbidity. Multivariate analysis adjusting for other prognostic factors showed that postoperative morbidity remained an independent prognostic factor for OS (hazard ratio [HR], 1.442; 95% confidence interval [CI], 1.136-1.831) and CSS (HR, 1.463; 95% CI, 1.063-2.013). There was no significant difference in survival according to the severity of complications. The following complications showed a significant association with unfavorable long-term survival: ascites (HR, 1.868 for OS, HR, 2.052 for CSS), wound complications (HR, 2.653 for OS, HR, 2.847 for CSS), and pulmonary complications (HR, 2.031 for OS, HR, 1.915 for CSS). Conclusions: Postoperative morbidity adversely impacted survival following total gastrectomy for gastric cancer. Among the different types of complications, ascites, wound complications, and pulmonary complications exhibited significant associations with long-term survival.