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.

Purpose: Radical cystectomy (RC) is associated with substantial postoperative morbidity, and unplanned readmission remains common despite advances in perioperative management. However, the association between postoperative readmission due to complications and oncologic outcomes after RC for bladder cancer has not been clearly defined. We evaluated the impact of postoperative readmission on overall survival (OS) and cancer-specific survival (CSS) after RC for bladder cancer. Materials and Methods: We retrospectively analyzed 3,972 patients who underwent RC for bladder cancer in a multicenter cohort. Postoperative readmission was defined as unplanned hospitalization within 90 days postsurgery due to surgery-related complications. Survival outcomes were assessed using the Kaplan-Meier method and compared using the log-rank test. Univariable and multivariable Cox proportional hazards regression analyses were performed to identify independent predictors of OS and CSS. Results: Among the study population, 916 patients (23.1%) experienced postoperative readmission. Baseline and perioperative characteristics were generally comparable between patients with and without readmission. Kaplan-Meier analyses demonstrated significantly worse OS and CSS among patients who experienced postoperative readmission (both log-rank p<0.001). In multivariable analyses adjusting for clinicopathological factors, postoperative readmission remained independently associated with worse OS (hazard ratio [HR], 1.654; 95% confidence interval [CI], 1.464–1.868; p<0.001) and CSS (HR, 1.761; 95% CI, 1.509–2.055; p<0.001). Conclusion Postoperative readmission within 90 days after RC was independently associated with inferior long-term oncologic outcomes. These findings suggest the importance of strategies aimed at preventing postoperative complications and subsequent readmission.

Objective: This study performed a longitudinal molecular characterization of P. multocidaisolates from pigs with respiratory lesions in South Korea (2016–2023), including subspecies identification, capsular serogrouping, virulence gene profiling, and multilocus sequence typing (MLST). Methods: A total of 1,358 pneumonic lung samples were collected from 960 pig farms between 2016 and 2023, yielding 169 P. multocida isolates. Subspecies were assigned by 16S rRNA gene sequencing. Capsular serogroups were determined using multiplex Virulence genes (pfhA, hgbB, tbpA, and toxA) were detected by PCR assays. MLST was conducted using the RIRDC scheme, and phylogenetic analysis of concatenated loci assessed clonal relationships. Results: Serogroup A predominated (109/169, 64.5%), followed by D (47/169, 27.8%) and B (3/169, 1.8%). Serogroups F and A/D were each detected once (0.6%), and 8 isolates were untypable (4.7%). Co-detection of hgbB and pfhA occurred in multiple isolates. Notably, two serogroup B isolates carried both genes, representing the first such finding in Korea and suggesting enhanced virulence potential. MLST identified 5 clonal complexes and 15 sequence types, including ST9 linked to serogroup B. Conclusions and Relevance: The emergence of serogroup B/ST9 isolates co-harboring hgbB and pfhA highlights evolving virulence patterns in Korean swine and supports continued molecular and genomic surveillance to guide control strategies and reduce health risks.

Objective: To provide a decade-long molecular and phenotypic characterization of APP isolates from Korean pig farms, focusing on the serovar distribution, apx-based toxingene profiles, and antimicrobial susceptibility. Methods: Between 2015 and 2025, 1,215 pneumonic lung samples from 965 pig farms yielded 132 APP isolates. The species identity was confirmed by 16S rRNA sequencing. The serovars were determined using capsule polysaccharide (CPS) gene-based multiplex polymerase chain reaction (PCR). Toxin genes (apxIA–apxIVA) were profiled, and the antimicrobial susceptibility to 29 agents was assessed by broth microdilution according to the Clinical and Laboratory Standards Institute guidelines. Results: Serovar 1 was predominant (66.7%), followed by serovars 5 (17.4%) and 2 (6.8%).CPS multiplex PCR identified three isolates (2.3%) as serovar 15, which displayed heterogeneous toxin gene profiles, including apxIICA-deficient profiles. Most isolates exhibited classical repeats-in-toxin operon arrangements, suggesting ongoing diversification of toxin gene profiles. High resistance rates were observed for oxytetracycline (90.9%) and florfenicol (50.8%), and recurrent multidrug-resistant combinations were frequently detected. Conclusions and Relevance: Serovar 1 is dominant in Korea, but the emergence of atypical toxin gene profiles in serovar 15 may carry immunological implications. Persistent resistance to older drug classes underscores the necessity for long-term molecular surveillance, evaluation of vaccine coverage against evolving strains, and enhanced antimicrobial stewardship to strengthen the control efforts for porcine pleuropneumonia in Korea.

Background: In February 2024, a sudden government policy to drastically increase medical school admissions triggered the mass resignations of medical trainees across South Korea, severely disrupting hospital operations. This study aimed to evaluate the impact of the resulting healthcare workforce disruptions on short-term clinical outcomes and the timing of colorectal cancer surgeries. Methods: This retrospective comparative study analyzed patients with colorectal cancer treated at two national university hospitals in Daegu and Gwangju, South Korea. Patients who first visited the colorectal surgery department between March and August of 2023 and 2024 were included. Data from 2020 to 2022 were used for extended comparisons. The primary outcome was the interval from initial outpatient visit to surgery. Secondary outcomes included treatment modality distribution, tumor staging, and postoperative complications. Results: A total of 895 patients in 2023 and 853 in 2024 were included. In 2024, only 39.5% of patients (337/853) underwent upfront surgery compared to 63.5% (569/895) in 2023. The median time to surgery increased from 30 days (interquartile range [IQR], 22–44 days) to 52 days (IQR, 30–72 days) (p=0.001). Clinical T3–4 tumors increased from 49.9% to 59.3% (p=0.018), lymph node-positive cases increased from 25.9% to 51.3% (p=0.001), and postoperative complication rates increased from 12.0% to 28.2% (p=0.001). Conclusion The abrupt healthcare workforce crisis in early 2024 significantly delayed colorectal cancer surgeries and was associated with worse short-term oncologic outcomes. These findings highlight the critical importance of maintaining a stable healthcare workforce to protect access to timely cancer care.

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.

Autoimmune hemolytic anemia (AIHA) is a rare immune-mediated disorder in children that can present as primary or secondary to other diseases. Here, we report an unusual case of steroid-refractory warm AIHA in an 11-year-old girl whose condition was ultimately cured after removal of a benign ovarian tumor. Despite receiving multiple lines of therapy—including corticosteroids, rituximab, cyclosporine, sirolimus, and mycophenolate mofetil—the patient experienced recurrent hemolysis and steroid dependence for nearly four years. Abdominopelvic imaging performed to evaluate fever revealed bilateral ovarian cystic lesions, including a left-sided dermoid cyst. Surgical resection of the tumor led to complete and sustained hematologic remission, with normalization of hemoglobin, bilirubin, and reticulocyte counts, allowing discontinuation of all immunosuppressive agents. No recurrence of hemolysis was observed during 18 months of follow-up. This case highlights the potential for benign ovarian tumors to act as a rare secondary cause of AIHA through paraneoplastic or immune cross-reactive mechanisms. Awareness of such associations is crucial when evaluating pediatric patients with refractory or relapsing AIHA, as identification and removal of an occult tumor may achieve definitive resolution of hemolysis and avoid long-term immunosuppression.

Background: and Purpose Criteria for amyloid-related imaging abnormalities in anti-amyloid therapy are based on T2* gradient-recalled echo (GRE), but susceptibility-weighted imaging (SWI) is widely used, creating uncertainty. This study quantitatively compared the detectability of SWI and GRE for cerebral microbleeds and established evidence supporting distinct microbleed criteria for each. Methods: A systematic review and meta-analysis were conducted following PRISMA guidelines. PubMed and Embase were searched for studies directly comparing SWI and GRE up to August 8, 2024. Study quality was assessed with QUADAS-2. The pooled proportion of microbleed detection and detection ratio were calculated. Subgroup analyses were performed based on magnetic field strength (1.5 T vs. 3 T) and SWI slice thickness (<2 mm vs. ≥2 mm), equipment vendor, and study quality. Results: Thirteen studies were included. SWI detected cerebral microbleeds approximately 1.6times more effectively than GRE. At 3.0 T and 1.5 T, SWI exhibited 1.7-fold and 1.5-fold greater detectability, respectively. SWI with thinner slices (<2 mm) showed a 1.9-fold improvement, while thicker slices (≥2 mm) showed a 1.3-fold improvement. Subgroup analyses revealed no significant differences between vendors (0.61 vs. 0.60, p=0.89), or by study quality (0.61 vs. 0.59,p=0.89). Conclusions SWI detects cerebral microbleeds about 1.6 times more effectively than GRE, highlighting important differences between the two techniques. Cautious exploration of adjusted thresholds may be needed, and prospective validation in therapy-specific cohorts will be essential before clinical application.

Background: and Purpose Whole-exome sequencing (WES) is a valuable tool for identifying causative mutations in adult moyamoya disease (MMD), thereby advancing our understanding of the genetic mechanisms underlying this condition. Here, we conducted the first WESbased association study aimed at identifying genetic modifiers implicated in MMD. Methods: This WES study involved 160 patients with MMD and 189 controls from a multicenter hospital-based biobank, and evaluated combined annotation-dependent depletion (CADD) scores. Mutant-allele frequencies were compared in 369,121 individuals derived from the UK Biobank (UKB) WES. Mutant-allele risk scores (MARSs) were created based on WESidentified mutations. Gene-based association analyses and pooled analyses in East-Asian populations were further performed. Results: Fourteen mutations reached the genome-wide significance criterion (p<5×10-8 ), among which the p.R4810K mutation in the ring finger protein 213 gene (RNF213) showed the strongest significance (odds ratio=117.4, p=8.54×10-24 ). Notably, two mutations—p.G576S (alpha-glucosidase [GAA]) and p.D54N (charged multivesicular body protein 6 [CHMP6])— exhibited high CADD scores of 32 and 25, respectively, whereas the RNF213 p.R4810K mutation demonstrated a moderate deleteriousness score of 10.63. Fourteen mutations exhibited significant differences in allele frequencies between patients and UKB controlled data (p<1×10-8 ).The MARS9 model (incorporating nine missense mutations) showed better predictability for MMD (90.89%). The analysis of gene-based associations revealed four candidate genes: GAA, RNF213, CHMP6, and CARD14 (p=5×10-19 to 4×10-7 ). The subsequent pooled analyses validated four mutations in East Asian populations: p.V1195M, p.D1331G, p.S2334N, and p.R4810K (p<3×10-8 ). Conclusions This pioneering study has corroborated the significance of p.R4810K and identified several causative mutations predisposing patients to MMD, which helps to improve the understanding of its polygenetic nature.

This study compared key health indicators of poor, older urban adults attending a free clinic with those of the general older population, using data from the 2023 Korea National Health and Nutrition Examination Survey (KNHANES). Methods: This cross-sectional comparative study included 60 adults aged ≥60 years who attended the Raphael Nanum Homeless Clinic in Seoul. Participants completed a questionnaire, underwent anthropometric assessment, and provided fasting blood samples for measurement of total cholesterol, low density lipoprotein (LDL)-cholesterol, and triglycerides (TG). Obesity, current smoking, monthly alcohol use, poor self-rated health, and strength exercise (≥ 2 days/week) were defined according to 2023 KNHANES criteria and compared with age-matched 2023 KNHANES estimates for adults aged ≥ 60 years using independent t-tests and two-proportion z-tests. Results: Participants were predominantly men (80.0%) with a mean age of 79.9 years; 70.0% reported no regular income, and 46.7% rated their health as poor. Compared with their 2023 KNHANES counterparts, the clinic group had a higher prevalence of obesity (50.0% vs. 35.0%), particularly among men, and a more atherogenic lipid profile characterized by higher LDL-cholesterol despite similar total cholesterol levels and lower TG. The prevalence of current smoking (3.3% vs. 10.6%) and monthly alcohol use (31.7% vs. 53.0%) was significantly lower, whereas participation in strength exercise was low in both groups, with no significant differences observed. Conclusion: Poor, older urban adults exhibited multidimensional health disparities, including obesity, adverse lipid profiles, and markedly poorer self-rated health, despite lower levels of smoking and alcohol consumption. Community-based interventions targeting nutrition, physical activity, and chronic disease management are needed to reduce health inequalities in this vulnerable population.