Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Objectives: This study investigated changes in toothbrushing in adolescents in response to public health policy changes during coronavirus disease 2019 (COVID-19) focusing on behavioral trends before, during, and after policy enforcement according to socio-demographic subgroups. Methods: Data from the Korean Youth Risk Behavior Survey (2018–2024) were divided into 3 periods: before (2018–2019), during (2020–2022), and after (2023–2024) the implementation of COVID-19 school restrictions. A total of 354 943 middle and high school students were included. The primary outcome variable was self-reported toothbrushing after lunch at school. Multivariable logistic regression was conducted, adjusting for confounders such as sex, academic performance, school level, school type, handwashing, and oral health status (toothache and gum bleeding). Results: The compliance rate for toothbrushing declined significantly during the restriction period across all groups. It varied by sex, school type, school level, health-related behaviors (drinking, smoking, handwashing), and oral health status. Female students, middle schoolers, students in single-sex schools, non-smokers, and those practicing hand hygiene showed higher compliance. After restrictions were lifted, toothbrushing rates improved but remained lower than pre-pandemic levels. Recovery of the toothbrushing rate was observed in most groups, particularly among female students, high schoolers, and those with positive health-related behaviors. However, academic performance and oral health status were not significantly associated with recovery rate in adjusted analyses. Conclusions This study highlights that adolescents’ health behaviors are highly sensitive to environmental and policy changes. Variations in compliance and recovery rates underscore the need for adolescent-centered policies that account for both compliance and recovery, especially during crises such as pandemics.

This study compared key health indicators of poor, older urban adults attending a free clinic with those of the general older population, using data from the 2023 Korea National Health and Nutrition Examination Survey (KNHANES). Methods: This cross-sectional comparative study included 60 adults aged ≥60 years who attended the Raphael Nanum Homeless Clinic in Seoul. Participants completed a questionnaire, underwent anthropometric assessment, and provided fasting blood samples for measurement of total cholesterol, low density lipoprotein (LDL)-cholesterol, and triglycerides (TG). Obesity, current smoking, monthly alcohol use, poor self-rated health, and strength exercise (≥ 2 days/week) were defined according to 2023 KNHANES criteria and compared with age-matched 2023 KNHANES estimates for adults aged ≥ 60 years using independent t-tests and two-proportion z-tests. Results: Participants were predominantly men (80.0%) with a mean age of 79.9 years; 70.0% reported no regular income, and 46.7% rated their health as poor. Compared with their 2023 KNHANES counterparts, the clinic group had a higher prevalence of obesity (50.0% vs. 35.0%), particularly among men, and a more atherogenic lipid profile characterized by higher LDL-cholesterol despite similar total cholesterol levels and lower TG. The prevalence of current smoking (3.3% vs. 10.6%) and monthly alcohol use (31.7% vs. 53.0%) was significantly lower, whereas participation in strength exercise was low in both groups, with no significant differences observed. Conclusion: Poor, older urban adults exhibited multidimensional health disparities, including obesity, adverse lipid profiles, and markedly poorer self-rated health, despite lower levels of smoking and alcohol consumption. Community-based interventions targeting nutrition, physical activity, and chronic disease management are needed to reduce health inequalities in this vulnerable population.

Purpose: Despite the increasing use of immediate breast reconstruction (IBR), its oncologic safety in the setting of neoadjuvant chemotherapy (NACT) needs to be comprehensively clarified in breast cancer management. The objective of the present study was to analyze the oncologic safety of IBR following NACT. Methods: In total, 587 patients with breast cancer who underwent a total mastectomy (TM) with IBR after NACT between 2008 and 2017 at a single institution were retrospectively reviewed. The reviewed patients with IBR following skin-sparing mastectomy (SSM) or nipple-sparing mastectomy (NSM) were matched 1:3 to patients who underwent TM alone after NACT. Matching variables included age, clinical T and N stages before NACT, response to NACT, pathologic T and N stages, and molecular subtypes. Results: After propensity score matching, 95 patients who underwent IBR following SSM/ NSM after NACT (IBR group) and 228 patients who underwent TM alone after NACT (TM group) were selected. The median follow-up period was 73 (range, 5–181) months after matching. After matching, there were no significant differences between the two groups in 5-year locoregional recurrence-free survival (88.8% vs. 91.2%, p = 0.516), disease-free survival (67.3% vs. 76.6%, p = 0.099), distant metastasis-free survival (71.9% vs. 81.9%, p = 0.057), or overall survival (84.1% vs. 91.5, p = 0.061) rates. In multivariate analyses, conducting IBR was not associated with increased risks for locoregional recurrence, any recurrence, distant metastasis, or overall death. Conclusion Our findings suggest that IBR following SSM/NSM elicits comparable long-term oncologic outcomes to those of TM alone in the setting of NACT.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: adenoma ≥10 mm in size; 3 to 5 (or more) adenomas; tubulovillous or villous adenoma; adenoma containing high-grade dysplasia; traditional serrated adenoma; sessile serrated lesion containing any grade of dysplasia; serrated polyp of at least 10 mm in size; and 3 to 5 (or more) sessile serrated lesions. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematologic disorder characterized by uncontrolled terminal complement activation. Eculizumab, a monoclonal antibody C5 inhibitor was introduced in Korea in 2009 and has been the standard treatment option for PNH. Methods: This study assessed the long-term efficacy/safety of eculizumab in PNH using real-world data from the Korean Health Insurance Review and Assessment Service. Eighty patients who initiated eculizumab from 2009–2020 were enrolled. Results: At eculizumab initiation, the median age was 51.5 years, lactate dehydrogenase (LDH) 6.8 × upper limit of normal, and granulocyte clone size 93.0%. All patients had at least one PNH-related complication before eculizumab initiation, including renal failure (n = 36), smooth muscle spasm (n = 24), thromboembolism (n = 20), and pulmonary hypertension (n = 15). The median (range) duration of eculizumab treatment was 52.7 (1.0, 127.3) months (338.6 total treated patient-years). Despite high disease activity in the study population before treatment initiation, overall survival was 96.2% and LDH levels were stabilized in most patients during treatment. PNH-related complications at treatment initiation were resolved in 44.4% of patients with renal failure, 95.8% with smooth muscle spasm, 70.0% with thromboembolism, and 26.7% with pulmonary hypertension. Extravascular hemolysis occurred in 28.8% of patients (n = 23; 0.09 per patient-year) and breakthrough hemolysis in 18.8% (n = 15; 0.06 per patient-year). No treatment discontinuation cases related to eculizumab were observed. Conclusion These data provided evidence for the long-term efficacy and safety of eculizumab in Korean PNH patients with high disease burdens.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for the management of advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: (1) adenoma ≥10 mm in size; (2) 3 to 5 (or more) adenomas; (3) tubulovillous or villous adenoma; (4) adenoma containing high-grade dysplasia; (5) traditional serrated adenoma; (6) sessile serrated lesion (SSL) containing any grade of dysplasia; (7) serrated polyp of at least 10 mm in size; and (8) 3 to 5 (or more) SSLs. More studies are needed to fully comprehend the patients most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: 1) adenoma ≥10 mm in size; 2) 3-5 (or more) adenomas; 3) tubulovillous or villous adenoma; 4) adenoma containing high-grade dysplasia; 5) traditional serrated adenoma; 6) sessile serrated lesion (SSL) containing any grade of dysplasia; 7) serrated polyp of at least 10 mm in size; and 8) 3-5 (or more) SSLs. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.