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.

Purpose: Adjuvant chemotherapy (AC) is recommended for muscle-invasive or lymph node-positive upper urinary tract urothelial carcinoma (UTUC) after radical nephroureterectomy (RNU). However, disease recurrences are frequently observed in pT1 disease, and AC may increase the risk of overtreatment in pT2 UTUC patients. This study aimed to validate a risk-adapted scoring model for selecting UTUC patients with ≤pT2 disease who would benefit from AC. Materials and Methods: We retrospectively analyzed 443 ≤pT2 UTUC patients who underwent RNU. A risk-adapted scoring model was applied, categorizing patients into low- or high-risk groups. Recurrence-free survival (RFS) and cancer-specific survival (CSS) were analyzed according to risk group. Results: Overall, 355 patients (80.1%) and 88 patients (19.9%) were categorized into the low- and high-risk groups, respectively, with the latter having higher pathological stages, concurrent carcinoma in situ, and synchronous bladder tumors. Disease recurrence occurred in 45 patients (10.2%), among whom 19 (5.4%) and 26 (29.5%) belonged to the low- and high-risk groups, respectively (p<0.001). High-risk patients had significantly shorter RFS (64.3% vs. 93.6% at 60 months; hazard ratio [HR] 13.66; p<0.001) and worse CSS (80.7% vs. 91.5% at 60 months; HR 4.25; p=0.002). Multivariate analysis confirmed that pT2 stage and the high-risk group were independent predictors of recurrence and cancer-specific death (p<0.001). Decision curve analysis for RFS showed larger net benefits with our model than with the T stage model. Conclusions The risk-adapted scoring model effectively predicts recurrence and identifies optimal candidates for AC post RNU in non-metastatic UTUC.

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: 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.

Purpose: Patients who undergo radical surgery for rectal cancer often experience low anterior resection syndrome (LARS). Symptoms of this syndrome include frequent bowel movements, gas incontinence, fecal incontinence, fragmentation, and urgency. The aim of this study was to investigate the convergent validity, discriminative validity, and reliability of the Korean version of the LARS score questionnaire. Methods: The English LARS score questionnaire was translated into Korean using the forward-and-back translation method. A total of 146 patients who underwent radical surgery for rectal cancer answered the Korean version of the LARS score questionnaire including an anchor question assessing the impact of bowel function. Participants answered the questionnaire once more after 2 weeks. Results: The Korean LARS score questionnaire showed high convergent validity in terms of high correlation between the LARS score and quality of life (perfect fit 55.5% vs. moderate fit 37.6% vs. no fit 6.8%, respectively; P < 0.001). The LARS score also showed good discriminative validity between groups of patients differing by sex (29 for males vs. 25 for females; P = 0.014), tumor level (29 for ≤8 cm vs. 24 for >8 cm; P = 0.021), and radiotherapy (32 for yes vs. 24 for no; P = 0.001). The LARS score also demonstrated high reliability at test-retest with no difference between scores at the first and second tests (intraclass correlation coefficient: Q1 = 0.932; Q2 = 0.909, Q3 = 0.944, Q4 = 0.931, and Q5 = 0.942; P < 0.001, respectively). Conclusion The Korean version of the LARS score questionnaire has proven to be a valid and reliable tool for measuring LARS in Korean patients with rectal cancer.

BACKGROUND/AIMS: Adenoma detection rate (ADR) is widely used as an index of colonoscopy quality management. Although advanced adenomas can be found less frequently than non-advanced adenomas, advanced adenomas have a higher clinical significance during screening for colorectal cancer. The aim of this study was to investigate the correlation between advanced and non-advanced ADR among colonoscopists. METHODS: This study is an observational study of a cohort of patients undergoing screening colonoscopy between 2009 and 2010. We collected the data on patients' characteristics and colonoscopic findings. The detection rates of adenoma and advanced adenoma were calculated. Logistic regression was used to determine the effects of variables on advanced adenoma detection, and spearman's rank-order correlation was used to evaluate the relationship between advanced ADR and ADR. RESULTS: A total of 561 patients underwent screening colonoscopy by 18 experienced colonoscopists. Most colonoscopists had adequate (>20%) ADRs. Logistic regression showed that increased patient age (OR 1.07 per 1 year increase, 95% CI 1.009-1.133, p=0.023) and male gender (OR 1.860, 95% CI 0.764-4.529, p=0.171) were associated with advanced ADR. When colonoscopists were divided into two groups on the basis of advanced ADR of 5%, ADR was also significantly higher in the group having higher level of advanced ADR. However, there was no correlation between advanced ADR and ADR among colonoscopists as an individual. CONCLUSIONS: Colonoscopists' advanced ADRs were independent of their ADRs, indicating that advanced ADR could be quite low even among colonoscopists with acceptable ADRs. Thus, there seems to be a limitation in using ADR as an adequate index of colonoscopy quality management.
Adenoma/*diagnosis ; Adult ; Aged ; Cohort Studies ; Colonoscopy ; Colorectal Neoplasms/*diagnosis ; Early Detection of Cancer ; Female ; Humans ; Logistic Models ; Male ; Middle Aged ; Neoplasm Staging ; Odds Ratio

BACKGROUND: Staphylococcus aureus (SA) has peculiar abilities to colonize the skin in atopic dermatitis (AD) patients. OBJECTIVE: We sought to determine the colonization rates of SA in acute and chronic skin lesions of AD patients, to find any difference in colonization rates according to age and to find the influences of total immunoglobulin E (IgE) and eosinophil counts to the colonization of SA. METHODS: We evaluated the total IgE level and eosinophil counts, and cultured SA from the skin lesions of 687 AD patients (131 acute and 556 chronic skin lesions) and 247 control urticaria patients (July 2009 to November 2010; Samsung Medical Center Dermatology Clinic, Seoul, Korea). RESULTS: The SA colonization rates were 74%, 38% and 3% in acute, chronic skin lesions and control skin, respectively, and they were increased with age in AD patients. The colonization rate in chronic skin lesions was higher in the high IgE/eosinophilia groups as compared to the normal IgE/eosinophil groups. CONCLUSION: The SA colonization rate was higher in AD patients and especially in acute lesions, and had a tendency to increase with age. As the colonization rates were only higher in the high IgE/eosinophilia groups of chronic skin lesions, we suggested that SA may invade the skin through barrier defects in acute skin lesions, but the colonization in chronic lesions may be orchestrated through many different factors.
Colon* ; Dermatitis, Atopic* ; Dermatology ; Eosinophils ; Humans ; Immunoglobulin E ; Immunoglobulins ; Skin* ; Staphylococcus aureus* ; Staphylococcus* ; Urticaria

BACKGROUND/AIMS: Conflicting data have been reported about the seasonal variation in flare-up of inflammatory bowel disease (IBD). The aim of this study was to assess the occurrence of seasonal variations in flare-up of IBD in the Korean population. METHODS: Patients with IBD, who underwent more than 1 year of follow-up and showed more than 1 episode of flare-up, were included. Flares of disease were refined as follows; receipt of a new prescription and increasing dose of corticosteroids, 5-ASA or immunosuppressant; hospitalized or operated due to development and worsening of symptoms; elevation of inflammatory marker due to worsening of Crohn's Disease Activity Index (CDAI) or Mayo score. In addition, for patients with more than two episodes of flare-up, they were investigated in a monthly and seasonal pattern. RESULTS: Of 573 patients with IBD, 46 patients with Crohn's disease and 61 patients with ulcerative colitis were enrolled. There was no association between month of the year and flare of Crohn's disease (P=0.06) or ulcerative colitis (P=0.58). Further, no association between season of the year and flare of Crohn's disease (P=0.06) or ulcerative colitis (P=0.68). However, in Crohn's disease who experience 2 or more flare-ups, symptoms occurred more frequently during winter, especially December (P=0.029). CONCLUSIONS: In the Korean population, there was no association of seasonal and monthly variation in flares of Crohn's disease and ulcerative colitis. However, in Crohn's disease, individuals with 2 flar-up or more, symptoms occurred more frequently during December.
Adrenal Cortex Hormones ; Colitis, Ulcerative ; Crohn Disease ; Follow-Up Studies ; Humans ; Inflammatory Bowel Diseases ; Prescriptions ; Seasons