Idiopathic inflammatory myopathies (IIMs) are heterogeneous immune-mediated muscle disorders with variable extramuscular manifestations and outcomes. Myositis-specific auto-antibodies (MSAs) have transformed the IIM field by enabling a serology-informed taxonomy based on distinct clinical phenotypes, prognostic trajectories, and therapeutic responses. Anti-Jo-1 and other antisynthetase antibodies characterize interstitial lung disease (ILD)-prone forms of disease; anti-MDA5 identifies patients at risk of rapidly progressive ILD and early mortality; anti-TIF1-γ and anti-NXP2 are indicative of cancer-associated myositis; anti-SRP and anti-HMGCR delineate necrotizing myopathies; and anti-cN1A supports the diagnosis of inclusion-body myositis. Beyond diagnosis, MSA profiles provide prognostic information, including about survival, relapse risk, and organ-specific complications, and they are increasingly being used to guide treatment decisions and predict biologic responsiveness. This review summarizes the diagnostic, prognostic, and therapeutic implications of MSAs across the IIM spectrum and highlight their growing importance in clinical practice for risk stratification and patient management.

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.

Although splenomegaly is typically uncommon in myelodysplastic syndromes (MDS), it is associated with reduced engraftment rates and poor survival outcomes. Despite its clinical significance, the incidence and genetic associations of splenomegaly in MDS remain understudied. To address this, we conducted a retrospective study of 27 patients with MDS at the Veterans Health Service Medical Center in South Korea. Based on computed tomography scan evaluation, splenomegaly was identified in 26% of patients with MDS, and significant associations with variants in ASXL1 (P = 0.0089 for null and missense/inframe variants) and RUNX1 (P = 0.042 for null variants) were observed, suggesting that these variants are linked to an increased risk of splenomegaly. Notably, one patient with ASXL1 and TET2 variants developed severe splenomegaly (spleen size, 29 cm) following granulocyte colony-stimulating factor (G-CSF) treatment, requiring splenectomy. This case suggests a potential interaction between specific genetic variants and G-CSF sensitivity, potentially exacerbating splenomegaly. Our findings suggest that the incidence of splenomegaly in patients with MDS, including mild cases, is likely underestimated and that ASXL1 and RUNX1 variants increase the risk of splenomegaly. Furthermore, careful monitoring for the development of severe splenomegaly during G-CSF treatment may be warranted in genetically susceptible individuals with MDS.

Purpose: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Materials and Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes.Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5,460 ESD cases from 5,250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

Background/Aims: Patients with postural tachycardia syndrome (POTS) commonly experience gastrointestinal (GI) symptoms. We aim to assess the feasibility and preliminary efficacy data for DA-9701, a prokinetic agent targeting 5-hy-droxytryptamine 1A, 5-hydroxytryptamine 4, and dopamine D 2 receptors, in patients with POTS. Methods: In a randomized, double-blind, placebo-controlled, single-center crossover trial, patients with POTS were given either 30 mg of DA-9701 or a placebo 3 times daily for eight weeks in a 1:1 ratio. After a 4-week washout, patients received the alternate treatment for another 8 weeks. The primary endpoint focused on assessing the change in GI symptoms (total Nepean Dyspepsia Index-Korean version [NDI-K] symptom score) from baseline over the 8 week-treatment period. Endpoints were assessed in all enrolled and randomized patients (intention-to-treat), and in those who completed the trial (per-protocol analysis). Results: Between January 2022 and August 2023, 24 patients were randomized (n = 12 per group), with 3 discontinuing after randomization. DA-9701 did not significantly improve primary endpoints for total NDI-K symptom scores in either the intention-to-treat (least-squares means, –13.9 vs. –9.5, P = 0.326) or per-protocol analyses (–17.2 vs –12.0, P = 0.242).Notably, a trend toward improvement in specific GI symptoms, such as upper abdominal pain, was observed in both intention-to-treat (–0.6 vs 0.7; P = 0.066) and per-protocol analyses (–0.9 vs 0.6; P = 0.045). No serious adverse events were observed. Conclusion DA-9701 did not improve GI symptoms in this crossover trial; however, its potential effect on specific GI symptoms merits further investigation.

Background: Seborrheic dermatitis (SD) is a chronic inflammatory scalp disorder associated with Malassezia dysbiosis and increased sebum production. AMPamide has been suggested to have anti-inflammatory and sebum-regulating effects, but its clinical efficacy and microbiome-modulating effects in SD remain unclear. Objective: To evaluate the clinical efficacy and scalp microbiome changes following 4 weeks of use of an AMPamide-containing shampoo in patients with SD. Methods: In this observational study, 30 patients with SD applied an AMPamide-containing shampoo for 4 consecutive weeks. Clinical outcomes, including sebum levels and overall severity scores, were assessed. Scalp bacterial and fungal communities were analyzed to evaluate α- and β-diversity and changes in Malassezia composition. Results: Treatment resulted in significant reductions in sebum levels and clinical severity scores, particularly in erythema, dandruff, and pruritus. Bacterial community composition remained largely stable, while fungal α-diversity increased, and β-diversity analysis revealed a decrease in the ratio of Malassezia restricta to Malassezia globosa. Conclusion AMPamide-containing shampoo was associated with improved clinical symptoms and a shift toward a more balanced fungal community composition in patients with SD, supporting its potential as a non-steroidal therapeutic option for SD.

Background: Obesity is a well-known risk factor for chronic kidney disease and its progression. However, the impact of obesity on the renal function of the elderly population is uncertain. We investigated the association between obesity and renal outcomes in the elderly. Methods: We analyzed 130,504 participants from the Korean National Health Insurance Service-Senior cohort. Obesity was classified according to body mass index (BMI), sex-specific waist circumference (WC), and the presence of metabolic syndrome. The primary outcome was renal function decline, defined as a decline in the estimated glomerular filtration rate (eGFR) of at least 50% from baseline or new-onset end-stage renal disease. Results: During a follow-up period of 559,531.1 person-years (median, 4.3 years), 2,486 participants (19.0%; incidence rate of 4.44 per 1,000 person-years) showed renal function decline. A multivariate Cox proportional hazards model revealed that BMI/WC was not associated with renal function decline. However, the group with metabolic syndrome had a significantly increased risk of renal function decline compared to the group without metabolic syndrome (adjusted hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.13–1.36). Compared with the non-metabolic syndrome group, the adjusted HRs (95% CI) for participants with one through five components were 0.96 (0.84–1.11), 1.10 (0.96–1.27), 1.24 (1.06–1.45), 1.37 (1.12–1.66), and 1.99 (1.42–2.79), respectively (p for trend < 0.001). Conclusion In elderly Korean adults, metabolic syndrome and the number of its components were associated with a higher risk of renal function decline, but BMI or WC was not significant.

Purpose: Atypical hyperplasia (AH) management remains controversial due to variable malignant disease progression rates. While Western studies report 10% to 25% upgrade rates, data from Asian populations, particularly from referral academic centers, are limited. We aimed to identify predictive factors for malignant upgrade in Korean women with AH at academic hospitals. Methods: This retrospective multi-institutional study analyzed 340 patients diagnosed with AH on initial biopsy who underwent subsequent excision at five Korean academic hospitals from 2000 to 2022. Malignant upgrade was defined as ductal carcinoma in situ or invasive cancer on the final pathology. Multivariate logistic regression was used to identify independent predictors of upgrades. Results: Among 340 patients (319 atypical ductal hyperplasia, 20 atypical lobular hyperplasia, and 1 mixed), 128 (37.6%) experienced a malignant upgrade, 98 (76.6%) to ductal carcinoma in situ, and 30 (23.4%) to invasive cancer. In multivariate analysis, multifocal atypia (odds ratio [OR], 25.61; 95% confidence interval [CI], 11.20–58.55; P<0.001) and Breast Imaging-Reporting and Data System 4c-5 lesions (OR, 11.02; 95% CI, 1.43–84.86; P=0.021) were significant predictors. Multifocal atypia showed an 84.4% upgrade rate. Core needle biopsy had higher upgrade rates than vacuum-assisted biopsy (45.2% vs. 20.0%; P<0.001). The upgrade rates decreased from 50% to 25% over the study period (P<0.05). Conclusion The 37.6% upgrade rate in this tertiary referral cohort exceeded that in Western reports, with multifocal atypia emerging as the strongest predictor. These findings support immediate excision for multifocal atypia while allowing individualized management for unifocal lesions with favorable imaging in Korean tertiary care settings.

Background: and Purpose: Clinicians typically use 2 methods to determine impairment in a specific cognitive domain based on the Seoul Neuropsychological Screening Battery, 2nd Edition: (1) identifying impairment when one or more subtests fall below the normal range (< mean −1.5 standard deviation), and (2) using the cognitive domain score. Because agreement between these methods may differ by the severity of cognitive impairment, this study examined their concordance in the overall sample and across Clinical Dementia Rating (CDR) levels. Methods: A total of 1,086 patients (age 74.27±9.62 years; education 9.07±4.77 years) were included. Concordance between subtest-based and domain score-based classifications was assessed for each cognitive domain using cross-tabulation analyses and Cohen’s kappa statistics. To assess the influence of the severity of cognitive impairment, analyses were conducted across CDR levels. Results: When impairment was defined as having at least one abnormal subtest, concordance rates were 90.8% for Attention, 88.8% for Language, 84.6% for Visuospatial Function, 74.3% for Memory, and 73.6% for Frontal/Executive Function. In the Frontal/ Executive Function domain, requiring 2 or more abnormal subtests increased concordance to 90.9%. CDR subgroup analyses showed that Memory concordance was particularly low in the CDR 0.5 group (65.8%) compared with the CDR 1 (85.5%) and CDR 2 (98.5%) groups. Conclusions Concordance between the 2 classification methods was moderately high for Attention, Language, and Visuospatial Function but substantially lower for Memory and Frontal/Executive Function, especially in individuals with mild cognitive impairment. These findings highlight the need to consider both subtest-level performance and domain scores when determining impairment in memory or frontal/executive function.