Purpose: Low-dose chest computed tomography (LDCT) is recommended for surveillance 2–3 years after curative resection of non-small cell lung cancer (NSCLC); however, supporting clinical evidence is limited. This study compared LDCT with contrast-enhanced chest computed tomography (CECT) in terms of recurrence detection and overall survival (OS) in patients 2 years after curative resection of NSCLC. Materials and Methods: Among patients who underwent curative resection for NSCLC between January 2011 and December 2017 and survived for 2 years without recurrence, 2,083 patients were included. Comparisons between the LDCT and CECT groups were performed in both the entire cohort and propensity score-matched cohort. The primary outcome was the difference in overall survival. Secondary outcomes included time-to-recurrence, recurrence-free survival, and post-recurrence survival in each group. Results: In the propensity score-matched population, the 5-year OS (96.0% for LDCT, 98.0% for CECT, p=0.097) and recurrence-free survival (RFS) (95.4% for LDCT, 96.0% for CECT, p=0.761) did not differ. The OS and RFS did not differ in subgroup analyses stratified by pathologic stage and histologic type. In the competing risk analysis, the overall 5-year cumulative incidence of recurrence did not differ between the two groups (4.56% for LDCT, 3.93% for CECT, p=0.765). When stratified by pathologic stage and histologic type, there was no significant difference in the cumulative incidence of recurrence. The distribution of recurrence sites did not differ between groups. Conclusion Similar OS and RFS were observed in LDCT and CECT surveillance in patients who achieved a 2-year disease-free status after curative resection for NSCLC.

Purpose: Radiotherapy (RT) remains a cornerstone of curative treatment for localized and locally advanced prostate cancer. However, dose escalation to improve tumor control is often constrained by the proximity of the rectum, which increases the risk of gastrointestinal (GI) and genitourinary toxicities. Biodegradable rectal spacers inserted between the prostate and rectum have emerged as an effective approach to reduce rectal radiation exposure. This guideline provides evidence-based recommendations on indications, contraindications, procedural standards, and clinical management for biodegradable rectal spacer insertion during prostate cancer RT. Materials and Methods: This guideline was developed by a multidisciplinary expert panel through a systematic review of the literature, analysis of international guidelines (National Comprehensive Cancer Network, European Association of Urology, American Society for Radiation Oncology), and expert consensus among radiation oncologists, radiologists, and urologists with clinical experience in spacer insertion. The strength of each recommendation and the level of evidence were classified according to the modified GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Results: Spacer insertion is conditionally recommended (Grade C, Level I) for patients receiving definitive external-beam RT without rectal invasion. It reduces the high-dose rectal irradiation volume (V70–75) by >50%, decreases acute GI toxicity, and helps maintain bowel-related quality of life. However, the benefit for late severe toxicity (grade 2 or higher) remains debated in recent meta-analyses. Contraindications include rectal invasion, anatomical inaccessibility, infection, and material hypersensitivity. Procedures should be performed under local anesthesia in a sterile environment by trained physicians. Short-course antibiotics and simulator-based training, including completion of multiple supervised cases, are advised. Conclusion Biodegradable rectal spacer insertion is clinically validated and effective in reducing acute rectal toxicity. Although pivotal trials demonstrated a favorable procedural safety profile, real-world postmarket data include reports of rare but severe procedural complications. This guideline provides standardized recommendations tailored to Korean clinical practice while remaining consistent with international standards, emphasizing the importance of operator training and careful patient selection.

Objective: To characterize toxin gene profiles and antimicrobial resistance among Clostridium perfringens isolated from diarrheic piglets in Korea. Methods: Fecal samples (n = 1,627) were collected from 286 farms in 2023–2024. Clostridium perfringens isolates (n = 410) were recovered under anaerobic conditions. Toxin genes (cpa, cpb, cpb2, cpe, etx, and iap) were detected by multiplex real-time polymerase chain reaction.Susceptibility to 18 antimicrobials was assessed by disc diffusion. Results: Type A strains (cpa alone [24.6%] or cpa+cpb2 [46.8%]) predominated; cpb2 and cpe were detected in 73.4% and 19.0% of isolates, respectively. Resistance was highest to bacitracin (94.9%), amoxicillin/clavulanic acid (79.8%), and florfenicol (81.5%). Conclusions and Relevance: In 2023–2024, type A isolates carrying cpb2 were the predominant toxinotype among Clostridium perfringens recovered from diarrheic piglets in Korea. The high prevalence of resistance to several commonly used agents supports strengthened antimicrobial stewardship and evaluation of alternative control strategies.

Purpose: To investigate the clinical characteristics of South Korean patients with pericentral retinitis pigmentosa (RP) and to identify clinical biomarkers associated with rapid visual acuity decline based on baseline factors. Methods: This retrospective study included 59 eyes of 31 patients diagnosed with pericentral RP. Comprehensive ophthalmological examinations and genetic sequencing were conducted to assess the baseline characteristics. For biomarker analysis, eyes were categorized into two groups based on the annual rate of change in visual acuity. The clinical findings of the two groups were evaluated to identify the biomarkers associated with rapid loss of visual acuity. Results: Patients with pericentral RP in this study exhibited a mean best-corrected visual acuity of 0.17 ± 0.23 in logarithm of the minimum angle of resolution. The visual field test showed annular or semicircular scotoma with relatively preserved periphery and 27 eyes (45.8%) exhibited no macular complications in optical coherence tomography. Genetic analysis identified genes associated with previous typical and pericentral RP studies but also highlighted that many genetic causes of pericentral RP remain unidentified. Of the 55 eyes for which the rate of visual acuity change could be estimated, 18 exhibited an annual decline of ≥10%, whereas 37 showed an annual decline of <10%. Male sex and prolonged b-wave latency on dark-adapted 0.01 electroretinogram correlated with rapid visual acuity decline in the multivariate analysis. Conclusions South Korean patients with pericentral RP exhibited a milder phenotype compared to typical RP patients reported in previous studies. Genetic analysis revealed heterogeneity, with mutations in some genes commonly associated with milder forms of RP. Male sex and prolonged b-wave latency on dark-adapted 0.01 electroretinogram were significant biomarkers for predicting rapid visual acuity decline. Monitoring initial b-wave latency is important for predicting visual decline, particularly in male patients with pericentral RP.

Background/Aims: As the number of lower gastrointestinal endoscopies and high-risk examinees increases, the incidence of adverse events associated with these endoscopies has also increased. Medical disputes and lawsuits related to adverse events are rapidly increasing. Methods: Medical disputes related to lower gastrointestinal endoscopy that had been filed in Korean Medical Dispute Mediation and Arbitration Agency (K-medi) from April 2012 to August 2020 were evaluated with the corresponding medical records and written appraisal. Facilities, patients, procedures, adverse events, and outcome-related variables related to medical disputes were analyzed. Results: As the number of lower gastrointestinal endoscopies in Korea increases each year, the number of medical disputes related to lower gastrointestinal endoscopy appraised by K-medi has also increased yearly during the same period. Among the 121 cases analyzed, 86 (71.1%) were conciliated and 35 (28.9%) were cosigned by prosecution. Perforations accounted for the largest proportion of cases (93 cases, 76.9%). Most patients (n = 119, 98.3%) underwent non-emergent procedures, and only 10 (8.3%) underwent them for therapeutic purposes. Approximately one-fifth of the patients (n = 25, 20.7%) died. Conclusions The number of medical disputes related to lower gastrointestinal endoscopy are increasing. To prevent this, it is important to review the data on existing cases and establish specific response guidelines.

Type 2 diabetes mellitus (T2DM) is marked by chronic hyperglycemia, gradually worsening β-cell failure, and insulin resistance. Glucotoxicity and oxidative stress cause β-cell failure by increasing reactive oxygen species (ROS) production, impairing insulin secretion, and disrupting transcription factors such as pancreatic and duodenal homeobox 1 (PDX-1) and musculoaponeurotic fibrosarcoma oncogene family A (MafA). Cluster determinant 36 (CD36), an essential glycoprotein responsible for fatty acid uptake, exacerbates oxidative stress and induces the apoptosis of β-cells under hyperglycemic conditions through pathways involving ceramide, thioredoxin-interacting protein (TXNIP), and Rac1-nicotinamide adenine dinucleotide phosphate oxidase (NOX)-mediated redoxosome formation. Targeting CD36 pathways has emerged as a promising therapeutic strategy. Oral hypoglycemic agents, such as metformin, teneligliptin, and pioglitazone, have shown protective effects on β-cells by enhancing antioxidant defenses. These agents reduce glucotoxicity via mechanisms such as suppressing CD36 expression and stabilizing mitochondrial function. Additionally, novel insights into the glutathione antioxidant system and its role in β-cell survival underscore its therapeutic potential. This review focuses on the key contribution of oxidative stress and CD36 to β-cell impairment, the therapeutic promise of antioxidants, and the need for further research to apply these findings in clinical practice. Promising strategies targeting these mechanisms may help preserve β-cell function and slow T2DM progression.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: s/Aims: We compared the postoperative outcomes of single-incision laparoscopic cholecystectomy (SILC) with those of single-incision robotic cholecystectomy (SIRC) using the da Vinci Xi and SP systems. Methods: We retrospectively analyzed data from 206 patients who underwent these procedures by a single surgeon between August 2020 and April 2022. Propensity score matching was used to adjust for confounders and evaluate outcomes. Results: SILC exhibited shorter operation times compared to SIRC with Xi and SP (44.9 ± 14.5 min vs. 55.3 ± 12.2 min vs. 55.2 ± 16.2 min, p < 0.001). SIRC with Xi had shorter docking times (6.2 ± 2.8 min vs. 10.3 ± 2.3 min, p < 0.001), while SIRC with SP demonstrated reduced console times (11.2 ± 2.4 min vs. 18.6 ± 8.0 min, p < 0.001). Pain scores and complications did not significantly differ between the groups. Conclusions Both SILC and SIRC showed comparable outcomes, with the SP system providing advantages such as reduced console time and fully articulated arms, likely reducing surgeon stress.