Purpose: Postoperative complications following gastric cancer surgery significantly impact patient outcomes, yet standardized definitions for these events have not been consistently applied across institutions in Korea. This study aimed to develop a consensus-based, standardized complication classification system specific to gastrectomy for gastric cancer as part of the Korean Quality Improvement Platform in Surgery (K-QIPS) initiative. Methods: As part of K-QIPS, a dedicated task force team (TFT) was formed with surgical experts from fourteen high-volume hospitals across Korea. The TFT conducted ten formal meetings to review existing literature and international guidelines, and incorporated findings from randomized controlled trials. The final complication list was developed through expert consensus and structured into a standardized framework. A Data Entry Manual was created to support consistent data collection by surgical clinical reviewers. Results: The TFT defined specific postoperative complications following gastrectomy for gastric cancer, including anastomotic leakage, duodenal stump leakage, pancreatic fistula, intra-abdominal and luminal bleeding, delayed gastric emptying, and internal hernia. Notably, internal hernia was described in standardized form for the first time. General complications were developed first and overlapped in part with the gastric cancer-specific list. The task force also produced a Data Entry Manual that provides practical instructions to ensure consistency and accuracy in complication reporting. Conclusion This nationwide consensus initiative established the first standardized complication classification system for gastric cancer surgery in Korea. The proposed definitions and data entry system are expected to improve complication reporting, enable multicenter research, support surgical quality benchmarking, and ultimately enhance patient outcomes.

Age-related macular degeneration (AMD) is a leading cause of blindness in people over 65 years old. Anti-vascular endothelial growth factor (VEGF) therapy is the first-line treatment for neovascular AMD (nAMD); however, fibrosis remains an unmet medical need due to the lack of effective medications. This study evaluated eight natural products from Celastrus orbiculatus, which has been reported to have anti-inflammatory effects, for their effects on the fibrotic pathological process as well as choroidal neovascularization (CNV). We investigated the half-maximal inhibitory concentration (IC 50) values of these compounds on VEGF and alphasmooth muscle actin (α-SMA, a fibrosis marker) expression-induced by human acute monocytic cell (THP-1) conditioned media in retinal pigment epithelium cells (ARPE-19). Four compounds reduced both VEGF and α-SMA at 10 μM, with three—Celafolin A-1, COFH5645, and COFH543435—showing the highest potency. Intravitreal injections of the compound in a mouse model of CNV induced by laser photocoagulation confirmed its efficacy. Celafolin A-1 significantly reduced α-SMA and VEGF expression and decreased hyper-reflective lesions and CNV areas. Binding affinity measurements using biolayer interferometry identified an interaction between Celafolin A-1 and crystallin alpha B (Cryab), a protein involved in stress responses and fibrosis. Celafolin A-1 reduced the expression levels of Cryab as well as its phosphorylated form at Ser45, indicating that its mechanism involves the regulation of Cryab phosphorylation. Taken together, Celafolin A-1 exhibits dual inhibitory effects on VEGF and fibrosis, suggesting it as a candidate for the treatment of nAMD.

Microglia are the resident immune cells of the brain; they respond rapidly to inflammatory stimuli and contribute to the progression of neurodegenerative diseases. Receptor-interacting protein kinase 3 (RIPK3) is known to mediate pro-inflammatory signaling and necroptosis, a form of regulated necrotic cell death. However, the role of RIPK3 in microglial activation remains unclear. This study aimed to investigate the role of RIPK3 in both in vitro and in vivo models of neuroinflammation and necroptosis using a selective RIPK3 inhibitor, GSK872. In lipopolysaccharide (LPS)-injected mice, GSK872 attenuated microglial activation, decreased the expression of pro-inflammatory mediators, and reduced the phosphorylation of RIPK3 and mixed lineage kinase domain-like protein (MLKL). In BV2 microglial cells, GSK872 suppressed the production of inflammatory mediators under both inflammatory and necroptotic conditions induced by LPS or LPS/Z-VAD. In particular, GSK872 reduced necroptosis-associated cell death and the release of HMGB1 and IL-1 in LPS/Z-VAD-treated cells. Detailed mechanistic studies revealed that GSK872 inhibits the c-Jun N-terminal kinase (JNK) pathway, while pharmacological inhibition of JNK using SP600125 recapitulates the effects of GSK872 on inflammatory and necroptotic markers. These results indicate that JNK plays a critical role in mediating the effects of GSK872. Notably, IL-1 released during necroptosis appears to contribute modestly to the phosphorylation of JNK and MLKL, indicating a potential feedback mechanism that reinforces necroptotic signaling. Our findings provide compelling evidence that the inhibition of RIPK3 by GSK872 alleviates neuroinflammatory responses and necroptotic cell death by modulating JNK signaling in activated microglia, offering a promising therapeutic strategy for neurodegenerative diseases.

Purpose: The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Materials and Methods: A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire. Results: Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ. Conclusion KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.

Purpose: Molecular characteristics of synchronous colorectal cancers (SCRCs) remain incompletely elucidated, despite their importance in targeted therapy selection. We compared the molecular characteristics and somatic mutations between SCRCs. Materials and Methods: This retrospective study (2012-2014) included 98 consecutive patients with surgically resected SCRCs. Molecular characteristics, including microsatellite instability (MSI) and tumor-infiltrating lymphocytes (TILs), were analyzed for all cancer lesions. The intertumoral heterogeneity of SCRCs was evaluated using whole-exome sequencing (WES) for 18 cancers from nine patients with at least one MSI-high (MSI-H) tumor. Results: Twelve patients had at least one MSI-H tumor; five showed discordant MSI status. Mucinous adenocarcinoma frequency and TIL density were higher in patients with at least one MSI-H tumor than in those with only microsatellite-stable tumors. WES revealed that, except one patient (6.5%), most synchronous cancers shared few variants in each patient (0.09%-0.36%). The concordance rates for BRAF, KRAS, NRAS, and PIK3CA, in synchronous cancers from each patient were 66.7%, 66.7%, 66.7%, and 55.6%, respectively. Conclusion Although synchronous cancers shared a mutated gene, the mutation subtypes differed. SCRCs exhibited 5.1% MSI status discordance rate and a high discordance rate in somatic mutational variants. As intertumoral heterogeneity may affect the targeted therapy response, molecular analysis of all tumors is recommended for patients with SCRCs.

Older adults living alone face challenges in managing diabetes, yet research on glycemic control in this group is limited. This study analyzed data from the Korean National Health and Nutrition Examination Survey (2016~2021) to identify factors associated with glycemic control in 453 older adults with diabetes living alone. Methods: Glycemic control was categorized as good (glycated hemoglobin [HbA1c]<7.0%) or poor (HbA1c≥7.0%). Complex sample logistic regression examined demographic, disease and health-related, behavioral, and psychological factors associated with glycemic control. Results: Older adults aged ≥80 years had better glycemic control than those aged 65~69 years, while a diabetes duration of ≥15 years and higher body mass index were linked to poorer control. Strength training 5~7 days per week was associated with better control, whereas non-adherence to a healthy diet was unexpectedly linked to better outcomes. Conclusion: These findings highlight the need for tailored interventions to improve diabetes self-management and support healthy aging among older adults living alone. They also offer practical insights into shaping community-based health programs and social support systems for this population.

Purpose: This study aimed to compare perioperative and postoperative outcomes of single-port laparoscopic articulated instrument-assisted versus da Vinci SP-assisted totally extraperitoneal (TEP) inguinal hernia repair using a propensity score-matched multi-institutional cohort. Methods: Between April 2022 and July 2025, 221 patients underwent TEP unilateral inguinal hernia repair at four institutions. Among them, 33 patients underwent da Vinci SP-assisted repair (Intuitive Surgical) and 188 underwent single-port laparoscopy using the articulated instrument, ArtiSential (LivsMed). Propensity score matching was performed in a 1:1 ratio based on demographic and clinical variables, resulting in 30 matched patients in each group. Perioperative outcomes and postoperative complications were analyzed. Results: After matching, baseline characteristics were well balanced between the groups.Operative time was significantly longer in the da Vinci SP group than in the ArtiSential group (median [interquartile range], 82.0 [67.5–105.0] vs. 35.0 [28.5–47.5] minutes; p < 0.001). No open conversions occurred, and conversions to transabdominal preperitoneal repair were rare and comparable. Mesh size selection differed significantly, with smaller meshes more frequently used in the da Vinci SP group (p < 0.001). Postoperative outcomes, including length of hospital stay, overall complication rates, chronic pain, and recurrence, were similar between the groups. No major complications, readmissions, or reoperations were observed. Conclusion Articulated instrument-assisted TEP inguinal hernia repair demonstrated a significantly shorter operative time than da Vinci SP-assisted repair, while perioperative safety and postoperative outcomes were comparable.

This study aimed to determine the prevalence of human epidermal growth factor receptor 2 (HER2)–ultralow breast cancer among cases initially classified as HER2 immunohistochemistry (IHC) 0 and assess interobserver variability in interpreting low-level HER2 expression. Methods: In this multicenter retrospective study, all invasive breast cancer cases diagnosed between January and December 2022 across 10 Korean institutions were retrieved. Institutional pathologists reexamined HER2 IHC slides originally reported as IHC 0 according to the 2018 American Society of Clinical Oncology/College of American Pathologists guidelines and reclassified them as HER2-null (0), HER2-ultralow (0+), or HER2-low (1+). Slides from 10% of HER2-null and HER2-ultralow cases were digitized for central review and independently assessed by two pathologists, with discrepancies resolved by consensus. Results: Among 8,026 cases, 2,836 cases (35.5%) were initially reported as IHC 0. Upon re-review, 1,673 (59.0%), 1,139 (40.2%), and 24 (0.8%) cases were reclassified as HER2-null, HER2-ultralow, and HER2-low, respectively. The prevalence of HER2-ultralow breast cancer varied considerably across institutions (23.7%–78.1%). Central review of 268 digitized cases showed concordance in 193 cases (72.0%). Among the 75 discordant cases, 54 tumors (72.0%) were upgraded from HER2-null to HER2-ultralow, and 18 (24.0%) tumors were upgraded from HER2-ultralow to HER2-low. Furthermore, two tumors (2.7%) were downgraded from HER2-ultralow to HER2-null. Conclusions: Approximately 40% of cases initially categorized as IHC 0 were reclassified as HER2-ultralow. The substantial inter-institutional variability observed in interpreting low-level HER2 expression highlights the need for standardized training and quality assurance to ensure accurate identification of patients eligible for HER2-targeted antibody–drug conjugates.

Objective: This study aims to compare the incidence of active tuberculosis (TB) among Korean patients with rheumatoid arthritis (RA) initiating treatment with tumor necrosis factor inhibitors (TNFi) or tofacitinib. Methods: Using the Korean National Health Insurance database, we conducted a nationwide, retrospective cohort study of RA patients who started TNFi or tofacitinib therapy between 2015 and 2018. We calculated the incidence rates of active TB based on the treatment type and results from latent tuberculosis infection (LTBI) screening tests. A multivariable Cox proportional hazards model was employed to evaluate the risk of active TB in RA patients beginning TNFi or tofacitinib treatment. Results: Among 3,382 RA patients (596 on tofacitinib and 2,786 on TNFi), LTBI screening was predominantly conducted using the IGRA (interferon-gamma release assays) test. Of these patients, 624 (18.5%) with a positive LTBI test received prophylactic treatment. No cases of active TB occurred in tofacitinib users, while 32 cases were observed in TNFi users. The adjusted hazard ratio for active TB in LTBI-positive patients was 5.47 (95% confidence interval 2.74 to 10.92) compared to LTBI-negative patients.In subgroup analyses, TB incidence was significantly higher among individuals aged over 65 years. Conclusion Despite LTBI treatment, active TB remains prevalent among RA patients on TNFi therapy and in those with positive LTBI tests.

Purpose: This developmental study explored the conceptual feasibility and applicability of a metaverse-based clinical assessment platform as a complementary tool to conventional objective structured clinical examinations in undergraduate medical education. Methods: A targeted literature review and expert consensus process were conducted to identify domains of clinical competence in which metaverse technologies could provide added value. Based on these findings, prototype virtual patient simulations were developed within a metaverse environment. Large language models (LLMs) were integrated to support dynamic, interactive history-taking simulations, and pilot modules for physical examination were also created. Results: Integration of LLMs into virtual patient scenarios enabled realistic, context-sensitive medical interviews, facilitating interactive dialogue between examinees and simulated patients. In contrast, physical examination modules faced technical limitations, particularly in replicating procedures requiring tactile or haptic feedback, such as palpation and percussion. Nevertheless, the metaverse environment enabled delivery of consistent and reproducible scenarios, supporting objective assessment of communication and diagnostic reasoning skills. Conclusion Metaverse-based simulations augmented by LLMs offer a promising approach to scalable and standardized clinical assessment, particularly within cognitive and interpersonal competency domains. Although current technological constraints limit the fidelity of physical examination simulations, rapid advancements in immersive and haptic technologies may help overcome these barriers in the near future. Further research is needed to evaluate the educational efficacy, validity, and feasibility of deploying such platforms in summative, high-stakes assessment contexts.