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.

Background: s/Aims: Pancreaticoduodenectomy (PD) is the standard treatment for periampullary tumors, but it is technically challenging. Evidence directly comparing open, laparoscopic, robotic, and hybrid approaches is limited. This study conducts a network meta-analysis (NMA) to compare the perioperative and oncologic outcomes of open PD (OPD), laparoscopic PD (LPD), robotic PD (RPD), and hybrid PD. Methods: We searched PubMed, EMBASE, and the Cochrane Library for studies published between January 1994 and August 2024.We included randomized controlled trials and comparative observational studies that evaluated at least two PD approaches. Perioperative outcomes were the primary endpoints, while oncologic safety served as a secondary endpoint. A random-effects NMA was performed, establishing treatment hierarchies through ranking probabilities (PROSPERO ID: CRD420250365864). Results: A total of 78 studies were included (5 randomized and 73 retrospective). RPD was associated with lower blood loss compared to OPD (mean difference [MD], –163.85 mL) and LPD (MD, –84.14 mL). Hospital stays were also shorter for RPD compared to OPD (MD, –2.50 days) and LPD (MD, –1.88 days). In contrast, OPD was the most time-efficient approach compared to LPD (MD, –77.61 minutes) and RPD (MD, –73.30 minutes). Mortality rates, severe complications, clinically relevant postoperative pancreatic fistula rates, and reoperation rates were comparable across all surgical approaches. In terms of oncologic safety, lymph node yield and R0 resection rates were similar for all modalities. Conclusions While OPD is the most time-efficient approach, RPD provides significant advantages in reducing intraoperative blood loss and shortening hospital stays compared to both LPD and OPD.

Purpose: This study evaluated long-term trends in gastric cancer epidemiology and survival with a focus on conditional relative survival (CRS). Materials and Methods: Using the Korea Central Cancer Registry, we analyzed 665,184 patients who were newly diagnosed with gastric cancer between 1999 and 2022.The study period was divided into four intervals: Period I (1999–2005), Period II (2006–2011), Period III (2012–2017), and Period IV (2018–2022). Temporal trends in the incidence and mortality were assessed using crude and age-standardized rates. Relative survival was estimated using the Ederer II method, and the 5-year CRS was calculated according to the survival duration after diagnosis. Results: The incidence of gastric cancer increased until 2011 and subsequently declined, with a marked decrease observed in 2020. Individuals aged ≥70 years consistently had the highest incidence rates. Mortality rates showed a sustained decline throughout the study period. The overall 5-year relative survival improved from 69.8% in Period II to 78.4% in Period IV. The 5-year CRS increased from 86.1% at 1 year after diagnosis to 96.3% at 5 years.Patients with localized stage maintained a 5-year CRS above 95% at 1 year after diagnosis, whereas those with regional and distant stages showed 5-year CRS that consistently remained below 95%. Conclusions The incidence and mortality rates of gastric cancer in Korea have declined over the past two decades, accompanied by improved survival outcomes. The CRS analysis suggests that long-term follow-up is warranted, with the optimal duration varying according to patient characteristics.

This video demonstrates the surgical technique of percutaneous endoscopic debridement and drainage (PEDD) for infectious spondylodiscitis performed under local anesthesia. Two representative cases are presented. The first case underwent transforaminal PEDD for L2–3 infectious spondylodiscitis, and the second case underwent combined transforaminal PEDD and drainage of a psoas abscess. In both cases, needle insertion was guided by C-arm fluoroscopy, followed by root block, discography, serial dilation, and insertion of a 3.7-mm endoscope. Under endoscopic visualization, necrotic disc material and infected granulation tissue were removed, and samples were collected for culture and biopsy. The procedure also enabled safe placement of a drainage catheter into the abscess cavity. Postoperatively, one patient improved with intravenous antibiotics after identification of Streptococcus constellatus, while the other was diagnosed with tuberculous spondylodiscitis and treated with antituberculosis therapy. Both patients showed gradual improvement in back pain and normalization of inflammatory markers. This video provides a detailed step-by-step guide to PEDD, highlighting its diagnostic and therapeutic advantages in infectious spondylodiscitis, as well as its educational value for surgeons learning full-endoscopic spine surgery.

Myopia, particularly high myopia, is a significant risk factor for several ocular pathologies including cataract, glaucoma, and retinal detachment. Excessive axial elongation associated with high myopia can induce biomechanical stretching, increasing the risk of serious complications like posterior staphyloma and myopic maculopathy. Global meta-analyses estimate that approximately 10 million people were visually impaired due to myopic maculopathy in 2015, with 3 million being blind. Recent nationwide surveys in South Korea revealed a prevalence of 65.4% for myopia and 6.9% for high myopia in children and adolescents, highlighting the urgent need for effective management. Delaying the onset and slowing the progression of myopia during childhood and adolescence is crucial for reducing the potential lifetime risk of these complications. This consensus statement, prepared by the Korean Myopia Society for the Korean Association for Pediatric Ophthalmology and Strabismus (KAPOS), reviews the current evidence for myopia control interventions and provides management strategies applicable to the South Korean clinical setting. Key interventions covered include lifestyle modifications (outdoor time, near work adjustment), optical methods (myopia-control spectacle lenses, dual-focus soft contact lenses, orthokeratology), and pharmacologic treatment (low-concentration atropine), as well as combination therapies. The statement also addresses patient selection, treatment outcome evaluation using spherical equivalent and axial length changes, and the crucial aspects related to treatment cessation and the rebound effect.

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.

Purpose: Metabolic bariatric surgery (MBS) efficacy and safety is established for older patients, but East Asian data are limited. This study aimed to evaluate the safety and efficacy of MBS by comparing older (≥55 years) and younger (<55 years) East Asian patients with obesity. Methods: This multicenter, retrospective review included 410 patients undergoing MBS from January to December 2019.Patients were stratified into the older group (OG, age ≥55 years; n = 39) and the younger group (YG, age <55 years; n = 371). We compared surgical safety, weight parameters, and comorbidity resolution rates. Results: The OG had lower mean body weight (97.9 ± 16.4 kg vs. 113.2 ± 23.1 kg, P < 0.001) but more comorbidities and lower average ABCD score for type 2 diabetes mellitus (T2DM) remission. Postoperative complication rate (12.8% vs. 7.5%, P = 0.400) and postoperative hospital stay (4.1 ± 1.8 days vs. 4.0 ± 8.9 days, P = 0.773) showed no significant differences.At 12 months, the percentage of total weight loss was significantly lower in the OG (23.7 ± 6.9% vs. 27.8 ± 8.4%, P = 0.014).Remission rates for T2DM (47.6% vs. 80.5%, P < 0.001), hypertension (34.6% vs. 57.5%, P = 0.073), and dyslipidemia (12.5% vs. 44.4%, P = 0.012) were also lower in the OG, yet still demonstrated clinically meaningful metabolic improvement. Conclusion MBS is a safe and effective treatment for older East Asians with obesity, offering substantial comorbidity resolution despite achieving a lower weight loss compared to the younger patients.

Alzheimer’s disease (AD) is characterized by progressive cognitive deterioration and significant depression. However, the mechanisms linking depression to AD pathology remain unclear. Here, we investigated whether Notch2 signaling mediates depressionlike behaviors in presenilin-2 (PS2) N141I mutant mice, an early-onset AD model. PS2 wild-type (WT) and mutant (MT) mice aged 12-15 months were subjected to unpredictable chronic mild stress (UCMS) for 4 weeks, followed by sucrose preference, tail-hanging, and forced swimming tests. Behavioral assessments showed that UCMS exacerbated anhedonia and immobility only in PS2 MT mice. Molecular analysis revealed concomitant increases in plasma corticosterone, hippocampal γ-secretase activity, and Notch2 expression, and elevated total and phosphorylated glucocorticoid receptor levels in PS2 MT-UCMS mice. Gene expression profiling of human hippocampal datasets confirmed upregulation of NOTCH2 in Alzheimer’s disease and depression.Pharmacological inhibition of γ-secretase and Notch signaling with DAPT normalizes depressive behavior, reduces corticosterone release, attenuates GR phosphorylation, and inhibits Notch2 signaling in PS2 MT mice. These findings identify Notch2 as a pivotal mediator linking chronic stress to molecular changes associated with depression and AD, and suggest that targeting Notch2 signaling may provide therapeutic benefits for comorbid mood and neurodegenerative disorders.