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.

Probiotics have gained increasing clinical attention as adjunctive treatment for lower gastrointestinal disorders. However, evidence supporting their therapeutic efficacy remains limited, particularly with regard to sex-related differences. This expert review provides evidence-based insights and practical recommendations for the use of probiotics in patients with irritable bowel syndrome (IBS), functional constipation (FC), and Clostridioides difficile infection (CDI), considering possible sex-related differences. Evidence from randomized controlled trials and meta-analyses indicates that probiotics can modestly improve global symptoms, abdominal pain, and bloating in IBS and enhance bowel movement frequency and stool consistency in FC. However, these effects are strain-specific and heterogeneous. Although clinical studies on probiotics in IBS have not confirmed significant sex-related differences, experimental animal studies using stress-induced IBS models have demonstrated sex-dependent responses to specific probiotic strains, supporting the biological plausibility of such differences. For CDI, the efficacy of probiotics in preventing primary or recurrent infections remains inconsistent across large trials, and current guidelines usually do not recommend their routine use. However, sex and age difference of immunology supports the clinical differences of CDI. Probiotics are generally considered safe for healthy individuals, although caution is advised in patients who are immunocompromised or critically ill. Clinicians should select probiotic products based on strain-specific clinical evidence, adequate viable doses, patient's characteristics, or patient’s sex. In conclusion, probiotics might play a role as adjunctive therapy for IBS and FC, with variability in responses influenced by microbial, host, and potential sex-related factors. Further research is needed to establish optimized personalized probiotic strategies.

Background/Aims: Spinal cord injury (SCI) frequently impairs defecation, severely affecting the quality of life. This study examines compensatory neural remodeling after SCI, focusing on basal colonic contractility, neural responses to electrical field stimulation, and alterations in excitatory cholinergic and inhibitory nitrergic pathways. Methods: Female Sprague–Dawley rats underwent either sham surgery or T10 spinal cord transection and were categorized into 3 groups: sham, 1-week post-SCI (acute), and 4-week post-SCI (chronic). Colonic contractility was assessed in an organ bath using electrical field stimulation in the presence of a nitric oxide synthase inhibitor. Neural protein expression was analyzed by immunofluorescence and Western blotting. Results: SCI produced region- and time-dependent impairments in colonic contractility, with distinct alterations in the proximal circular and longitudinal muscles across acute and chronic phases. Neural excitability shifted dynamically, showing enhanced excitatory activity in the proximal longitudinal muscle at 1-week and the distal circular muscle at 4-week post-SCI. Protein analysis revealed increased neuronal nitric oxide synthase in the proximal colon, decreasedsoluble guanylyl cyclase in the distal colon, upregulated muscarinic M3 receptor in the proximal colon, and reduced vaso-active intestinal peptide receptor 1 in both proximal and distal regions. Conclusion SCI induces spatiotemporal remodeling of excitatory and inhibitory neural pathways, contributing to colonic dysmotility and revealing potential targets for therapeutic intervention.

Purpose: This study aimed to evaluate age- and sex-specific dietary vitamin B12 intake among Koreans, assess adequacy relative to the 2025 Korean Dietary Reference Intakes, and identify major food groups using nationally representative data from the 2022–2024 Korea National Health and Nutrition Examination Survey (KNHANES). Methods: Data from 19,191 participants in the KNHANES 2022–2024 aged1 year and older were analyzed after excluding individuals with extreme energy intake values. Individual vitamin B12 intake was calculated based on 24-hour dietary recall data using the Korean National Standard Food Composition Database (version 10.3). Intake levels were evaluated against age- and sex-specific Estimated Average Requirement (EAR) and Recommended Nutrient Intake (RNI) values. Complex sample general linear models and cross-tabulation analyses were conducted to examine differences in intake and adequacy. Results: The mean vitamin B12 intake of the study population was 8.27 μg/day, exceeding the RNI in most age groups. The proportion of individuals meeting or exceeding the RNI was generally high; however, the prevalence of intake below the EAR increased with age, particularly among older women, approximately 35% of whom were at risk of inadequate intake. Animal-based foods, including fish and shellfish, meat, eggs, and dairy products, were the primary contributors to vitamin B12 intake. Adults and older adults with intake below the RNI consumed significantly lower amounts of these food groups compared with those meeting the RNI. Conclusion Although overall vitamin B12 intake among Koreans appears sufficient, older adults remain at increased risk of insufficient intake. Continuous monitoring of vitamin B12 nutritional status and targeted dietary strategies, with a focus on older populations, is warranted to prevent potential deficiencies.

Probiotics have gained increasing clinical attention as adjunctive treatment for lower gastrointestinal disorders. However, evidence supporting their therapeutic efficacy remains limited, particularly with regard to sex-related differences. This expert review provides evidence-based insights and practical recommendations for the use of probiotics in patients with irritable bowel syndrome (IBS), functional constipation (FC), and Clostridioides difficile infection (CDI), considering possible sex-related differences. Evidence from randomized controlled trials and meta-analyses indicates that probiotics can modestly improve global symptoms, abdominal pain, and bloating in IBS and enhance bowel movement frequency and stool consistency in FC. However, these effects are strain-specific and heterogeneous. Although clinical studies on probiotics in IBS have not confirmed significant sex-related differences, experimental animal studies using stress-induced IBS models have demonstrated sex-dependent responses to specific probiotic strains, supporting the biological plausibility of such differences. For CDI, the efficacy of probiotics in preventing primary or recurrent infections remains inconsistent across large trials, and current guidelines usually do not recommend their routine use. However, sex- and age-related immunologic differences support the clinical differences of CDI. Probiotics are generally considered safe for healthy individuals, although caution is advised in patients who are immunocompromised or critically ill. Clinicians should select probiotic products based on strain-specific clinical evidence, adequate viable doses, patient characteristics and sex. In conclusion, probiotics might play a role as adjunctive therapy for IBS and FC, with variability in responses influenced by microbial, host, and potential sex-related factors. Further research is needed to establish optimized personalized probiotic strategies.

Pediatric kidney disease has a relatively lower prevalence than do other pediatric conditions and has a notably different etiology from kidney diseases observed in adults. Furthermore, the pediatric population is unique in that they experience ongoing growth and development, distinguishing them from adult patients. Consequently, pediatric patients with kidney disease require more specialized and meticulous nutritional management than do adults. To address this need and promote optimal dietary practices for pediatric patients with kidney disease, pediatric nephrologists from the Korean Society of Pediatric Nephrology and nutritionists from the Korean Society of Clinical Nutrition have collaborated to establish nutritional guidelines specifically tailored to Korean dietary patterns. These guidelines offer detailed, nutrient-specific recommendations covering energy, protein, calcium, phosphorus, and potassium consumption while providing practical, culturally relevant guidance intended to support both pediatric patients and their caregivers.

Objective: To investigate the relationship between oral health, cognitive function, and quality of life (QoL) in elderly patients with schizophrenia. Methods: This cross-sectional study included 92 patients with schizophrenia, aged 60-90 years. Assessments included the Geriatric Oral Health Assessment Index (GOHAI), Consortium to Establish a Registry for Alzheimer’s Disease-Korean version, Schizophrenia Quality of Life Scale (SQLS), and Clinical Global Impression-Severity (CGI-S). Correlation and multiple regression analyses were performed. Results: GOHAI scores were significantly and negatively correlated with SQLS (r=-0.323) and CGI-S (r=-0.230). Multiple regression confirmed GOHAI as an independent predictor of SQLS (β=-0.325, p=0.001) after controlling for demographic and clinical variables. Furthermore, anticholinergic drug use did not significantly moderate the positive impact of oral health on QoL. Conclusion Improving oral health is directly associated with better subjective QoL in elderly patients with schizophrenia, independent of objective cognitive decline or anticholinergic burden. Integrated psychiatric-dental care is crucial for this population.

Background: Basal cell carcinomas (BCCs) are often misdiagnosed as benign lesions, leading to inappropriate laser ablation. Misidentification may cause delays in proper diagnosis and surgical intervention, potentially affecting patient outcomes. Objective: We investigated the percentage of patients with BCC who were inappropriately treated with laser ablation following the introduction of dermoscopic examination reimbursement and analyzed their clinical and histological characteristics. Methods: We retrospectively reviewed the data of 106 patients with histologically confirmed BCC after reimbursement for dermoscopic examinations was implemented. Results: Among the 106 patients pathologically diagnosed with BCC, 11 patients (10.4%) had a history of laser ablation after being misdiagnosed with a benign lesion. All patients had pigmented BCCs on their faces, with the cheeks and nose (36.4% each) being the most frequent sites of involvement. The mean time between laser treatment and hospital visits was 30.9 months, and six patients (54.5%) were diagnosed with BCC within 1∼5 years after laser ablation. Of the 11 patients, six were treated by dermatologists, two by non-dermatologists, and two by non-licensed personnel. Nine patients showed at least one classic dermoscopic pattern, and the most common dermoscopic finding was the presence of multiple blue/gray globules (7/10, 70.0%). No recurrence after wide excision was observed during the last follow-up. Conclusion Despite dermoscopic examination reimbursement, our findings indicate that approximately 10.0% of BCCs are still misdiagnosed as benign lesions, as reported in a previous study. Therefore, when a malignancy is suspected, dermoscopic examination and biopsy should be considered to ensure an accurate diagnosis and facilitate appropriate treatment.

Purpose: This study assessed the validity of the hospital standardized mortality ratio (HSMR) risk-adjusted model by comparing models that include clinical information and the current model based on administrative information in South Korea. Materials and Methods: The data of 53976 inpatients were analyzed. The current HSMR risk-adjusted model (Model 1) adjusts for sex, age, health coverage, emergency hospitalization status, main diagnosis, surgery status, and Charlson Comorbidity Index (CCI) using administrative data. As candidate variables, among clinical information, the American Society of Anesthesiologists score, Acute Physiology and Chronic Health Evaluation (APACHE) II, Simplified Acute Physiology Score (SAPS) 3, present on admission CCI, and cancer stage were collected. Surgery status, intensive care in the intensive care unit, and CCI were selected as proxy variables among administrative data. In-hospital death was defined as the dependent variable, and a logistic regression analysis was performed. The statistical performance of each model was compared using C-index values. Results: There was a strong correlation between variables in the administrative data and those in the medical records. The C-index of the existing model (Model 1) was 0.785; Model 2, which included all clinical data, had a higher C-index of 0.857. In Model 4, in which APACHE II and SAPS 3 were replaced with variables recorded in the administrative data from Model 2, the C-index further increased to 0.863. Conclusion The HSMR assessment model improved when clinical data were adjusted. Simultaneously, the validity of the evaluation method could be secured even if some of the clinical information was replaced with the information in the administrative data.

Background/Aims: The Korean guidelines for Helicobacter pylori treatment were revised in 2020, however, the extent of adherence to these guidelines in clinical practice remains unclear. Herein, we initiated a prospective, nationwide, multicenter registry study in 2021 to evaluate the current management of H.pylori infection in Korea. Methods: This interim report describes the adherence to the revised guidelines and their impact on firstline eradication rates. Data on patient demographics, diagnoses, treatments, and eradication outcomes were collected using a web-based electronic case report form. Results: A total of 7,261 patients from 66 hospitals who received first-line treatment were analyzed.The modified intention-to-treat eradication rate for first-line treatment was 81.0%, with 80.4% of the prescriptions adhering to the revised guidelines. The most commonly prescribed regimen was the 14-day clarithromycin-based triple therapy (CTT; 42.0%), followed by tailored therapy (TT; 21.2%), 7-day CTT (14.1%), and 10-day concomitant therapy (CT; 10.1%). Time-trend analysis demonstrated significant increases in guideline adherence and the use of 10-day CT and TT, along with a decrease in the use of 7-day CTT (all p<0.001). Multivariate logistic regression analysis revealed that guideline adherence was significantly associated with first-line eradication success (odds ratio, 2.03; 95% confidence interval, 1.61 to 2.56; p<0.001). Conclusions The revised guidelines for the treatment of H. pylori infection have been increasingly adopted in routine clinical practice in Korea, which may have contributed to improved first-line eradication rates. Notably, the 14-day CTT, 10-day CT, and TT regimens are emerging as the preferred first-line treatment options among Korean physicians.