Background/Aims: Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC. Methods: This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC. Results: This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival. Conclusions Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

Background/Aims: Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC. Methods: This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC. Results: This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival. Conclusions Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

Background/Aims: Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC. Methods: This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC. Results: This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival. Conclusions Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

Background/Aims: Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC. Methods: This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC. Results: This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival. Conclusions Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

Background: s/Aims: Systematic investigations into the prognostic impact of the longitudinal tumor location in gallbladder cancer (GBC) remain insufficient. To address the limitations of our pilot study, we conducted a multicenter investigation to clarify the impact of the longitudinal tumor location on the oncological outcomes of GBC. Methods: A retrospective multicenter study was conducted on 372 patients undergoing radical resections for GBC from January 2010 to December 2019 across seven hospitals that belong to the Daejeon–Chungcheong branch of the Korean Association of Hepato-Biliary-Pancreatic Surgery. Patients were divided into GBC in the fundus/body (FB-GBC) and GBC in the neck/cystic duct (NC-GBC) groups, based on the longitudinal tumor location. Results: Of 372 patients, 282 had FB-GBC, while 90 had NC-GBC. NC-GBC was associated with more frequent elevation of preoperative carbohydrate antigen (CA) 19-9 levels, requirement for more extensive surgery, more advanced histologic grade and tumor stages, more frequent lymphovascular and perineural invasion, lower R0 resection rates, higher recurrence rates, and worse 5-year overall and disease-free survival rates. Propensity score matching analysis confirmed these findings, showing lower R0 resection rates, higher recurrence rates, and worse survival rates in the NC-GBC group. Multivariate analysis identified elevated preoperative CA 19-9 levels, lymph node metastasis, and non-R0 resection as independent prognostic factors, but not longitudinal tumor location. Conclusions NC-GBC exhibits more frequent elevation of preoperative CA 19-9 levels, more advanced histologic grade and tumor stages, lower R0 resection rates, and poorer overall and disease-free survival rates, compared to FB-GBC. However, the longitudinal tumor location was not analyzed as an independent prognostic factor.

Background: s/Aims: Systematic investigations into the prognostic impact of the longitudinal tumor location in gallbladder cancer (GBC) remain insufficient. To address the limitations of our pilot study, we conducted a multicenter investigation to clarify the impact of the longitudinal tumor location on the oncological outcomes of GBC. Methods: A retrospective multicenter study was conducted on 372 patients undergoing radical resections for GBC from January 2010 to December 2019 across seven hospitals that belong to the Daejeon–Chungcheong branch of the Korean Association of Hepato-Biliary-Pancreatic Surgery. Patients were divided into GBC in the fundus/body (FB-GBC) and GBC in the neck/cystic duct (NC-GBC) groups, based on the longitudinal tumor location. Results: Of 372 patients, 282 had FB-GBC, while 90 had NC-GBC. NC-GBC was associated with more frequent elevation of preoperative carbohydrate antigen (CA) 19-9 levels, requirement for more extensive surgery, more advanced histologic grade and tumor stages, more frequent lymphovascular and perineural invasion, lower R0 resection rates, higher recurrence rates, and worse 5-year overall and disease-free survival rates. Propensity score matching analysis confirmed these findings, showing lower R0 resection rates, higher recurrence rates, and worse survival rates in the NC-GBC group. Multivariate analysis identified elevated preoperative CA 19-9 levels, lymph node metastasis, and non-R0 resection as independent prognostic factors, but not longitudinal tumor location. Conclusions NC-GBC exhibits more frequent elevation of preoperative CA 19-9 levels, more advanced histologic grade and tumor stages, lower R0 resection rates, and poorer overall and disease-free survival rates, compared to FB-GBC. However, the longitudinal tumor location was not analyzed as an independent prognostic factor.

Background: s/Aims: Systematic investigations into the prognostic impact of the longitudinal tumor location in gallbladder cancer (GBC) remain insufficient. To address the limitations of our pilot study, we conducted a multicenter investigation to clarify the impact of the longitudinal tumor location on the oncological outcomes of GBC. Methods: A retrospective multicenter study was conducted on 372 patients undergoing radical resections for GBC from January 2010 to December 2019 across seven hospitals that belong to the Daejeon–Chungcheong branch of the Korean Association of Hepato-Biliary-Pancreatic Surgery. Patients were divided into GBC in the fundus/body (FB-GBC) and GBC in the neck/cystic duct (NC-GBC) groups, based on the longitudinal tumor location. Results: Of 372 patients, 282 had FB-GBC, while 90 had NC-GBC. NC-GBC was associated with more frequent elevation of preoperative carbohydrate antigen (CA) 19-9 levels, requirement for more extensive surgery, more advanced histologic grade and tumor stages, more frequent lymphovascular and perineural invasion, lower R0 resection rates, higher recurrence rates, and worse 5-year overall and disease-free survival rates. Propensity score matching analysis confirmed these findings, showing lower R0 resection rates, higher recurrence rates, and worse survival rates in the NC-GBC group. Multivariate analysis identified elevated preoperative CA 19-9 levels, lymph node metastasis, and non-R0 resection as independent prognostic factors, but not longitudinal tumor location. Conclusions NC-GBC exhibits more frequent elevation of preoperative CA 19-9 levels, more advanced histologic grade and tumor stages, lower R0 resection rates, and poorer overall and disease-free survival rates, compared to FB-GBC. However, the longitudinal tumor location was not analyzed as an independent prognostic factor.

Background: s/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

This study was conducted to investigate potential differences in vaccine efficacy between patients undergoing palliative chemotherapy and receiving adjuvant chemotherapy. Additionally, the study proved the influence of vaccination timing on vaccine efficacy during active chemotherapy. Anti-receptor-binding domain (RBD) IgG binding antibody assays and surrogate neutralizing antibody assays were performed after BNT162b2 or mRNA-1273 vaccination in 45 solid cancer patients (23 adjuvant and 22 palliative chemotherapy) and in 24 healthy controls before vaccination (baseline), at every two to four weeks after the first (post-dose 1) and the second vaccination (post-dose 2). The levels of anti-RBD IgG and neutralizing antibodies increased significantly from baseline through post-dose 1 to post-dose 2 in all three groups. At the post-dose 1, the anti-RBD IgG and neutralizing antibody levels were significantly lower in cancer patients than in healthy controls. However, by post-dose 2, the seropositivity of anti-RBD IgG and neutralizing antibodies uniformly reached 100% across all groups, with no significant disparity in antibody levels among the three groups. Moreover, the antibody titers were not significantly different between patients with a vaccine and chemotherapy interval of more than 14 days or those with less than 14 days. This study demonstrated that after second doses of mRNA COVID-19 vaccines, humoral immune responses in patients receiving chemotherapy were comparable to those of healthy controls, regardless of whether the purpose of the anti-cancer treatment was palliative or adjuvant. Furthermore, the timing of vaccination did not affect the level of humoral immunity after the second vaccination.

Background: and Purpose Excess or insufficient sleep, irregular sleep-wake patterns, and an extreme early or late chronotypes adversely impact physical and mental health. Changes in sleep characteristics should therefore be tracked, and factors that contribute to poor sleep should be identified. We investigated the changes in sleep patterns among South Korean adults during 2009–2018. Methods: Using data of a representative sample of South Korean adults from the 2009 (n= 2,658, 48.5% males; age=44.5±15.0 years old [mean±standard deviation], age range=19–86 years) and 2018 (n=2,389, 49.1% males; age=47.9±16.3 years, age range=19–92 years) Korean Headache-Sleep Study, we explored changes in sleep timing, sleep duration, chronotype, and social jetlag (SJL). Logistic regression analysis was used to examine the association between average sleep duration and depression. Results: From 2009 to 2018, bedtimes were advanced by 10 and 25 min on workdays and free days, respectively. Meanwhile, wake-up times were advanced by 13 min and delayed by 12 min on workdays and free days, respectively. The average sleep duration significantly decreased from 7.45 h to 7.13 h. The prevalence of short sleep duration (<7 h) increased, whereas that of long sleep duration (≥8 h) decreased. A circadian preference toward eveningness and SJL increased. The prevalence of depression increased from 4.6% to 8.4%, and there were significant reverse J-shaped and U-shaped associations between average sleep duration and depression in 2009 and 2018, respectively. Conclusions Changes in sleep patterns and the association between sleep duration and depressive mood were determined from a representative sample of the South Korean adult population. Interventions to modify sleep behaviors might improve public health.