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.

Background: To investigate the fracture risks associated with anti-diabetic drugs in older women with type 2 diabetes mellitus (T2DM), who are particularly susceptible to skeletal fragility. Methods: Using data from the Korean National Health Insurance Service, this nested case-control study included 10,104 older women with T2DM and osteoporotic fractures (aged 66.5±3.4 years) matched in a 1:3 ratio with controls by birthdate, Charlson Comorbidity Index, and cohort entry date. We analyzed the odds of major osteoporotic fracture (MOF), vertebral fracture (VF), and non-VF (NVF) in users of sulfonylurea, thiazolidinedione (TZD), dipeptidyl peptidase-4 inhibitor, and sodium-glucose cotransporter 2 inhibitor (SGLT2i), compared to metformin (Met)-only users using multivariable logistic regression. Results: During a follow-up period of 3.8±2.8 years, TZD users had a higher risk of MOF than Met-only users (odds ratio [OR], 1.35; 95% confidence interval [CI], 1.19-1.53; P<0.001). Risks of VF and NVF were also increased in the TZD group (OR, 1.21; 95% CI 1.03-1.42; P=0.022 and OR, 1.32; 95% CI 1.14-1.52; P<0.001, respectively). No significant differences were observed in other drug groups. The increased risk of VF and NVF in the TZD group were particularly pronounced in patients with normal or osteopenic bone mineral density (BMD) and in those with normal body mass index (BMI), respectively. Conclusions In older women with T2DM, TZD use was associated with increased VF and NVF risks, particularly among those with normal or osteopenic BMD and normal BMI. SGLT2i showed no increased risk, but further large-scale studies are needed to confirm its skeletal safety.

Purpose: This study aimed to develop and implement an antimicrobial stewardship education program for physician assistant nurses and to evaluate its effects on their knowledge and clinical performance. Methods: A quasi-experimental, single-group pre-post design was conducted with 50 physician assistant nurses at a university hospital in Seoul, Republic of Korea. The antimicrobial stewardship education program, developed using the ADDIE model, consisted of 12 sessions including lectures and case-based learning (CBL)-based discussions.Knowledge was measured before and immediately after the intervention, while performance was assessed pre-intervention and four weeks post-program. Data were analyzed using paired t-tests, Wilcoxon signed-rank tests, and analysis of covariance (ANCOVA). Results: Knowledge scores significantly improved from 44.65±7.45 to 58.50±10.11 (p<.001), and all subdomains showed significant increases (p<.001). Performance scores increased from 3.68±0.77 to 4.28±0.68 (p<.001). Knowledge gain did not differ significantly between the medical and surgical departments (p=.710). Likewise, after adjusting for pre-test scores, no significant difference in performance improvement was observed between the two departments (ANCOVA, p=.170). These results indicate that the program was effective across both departments regardless of their characteristics. Conclusion The antimicrobial stewardship education program improved both knowledge and performance among physician assistant nurses. This program may contribute to the standardization of antimicrobial stewardship education and to appropriate antimicrobial use and the reduction of antimicrobial resistance.

Purpose: We compared short-term clinical outcomes after cataract surgery with implantation of a novel refractive extended depth-of-focus TECNIS PureSee intraocular lens (IOL) between patients with stage 1 epiretinal membrane (ERM)—characterized by a thin membrane over the macula with preserved foveal depression―and those with a normal retina. Methods: This retrospective study included 60 eyes of 60 patients who underwent cataract surgery with implantation of the TECNIS PureSee IOL between January 2024 and January 2025: 30 eyes with stage 1 ERM and 30 eyes with a normal retina. Preoperative characteristics, including age, sex distribution, cataract severity, corrected distance visual acuity (CDVA), and higher-order aberrations, were compared between groups, as were IOL power and target refraction. Postoperative outcomes at 1 month―including CDVA, uncorrected distance, intermediate, and near visual acuity, ocular aberrations, and contrast sensitivity―were evaluated. Results: There were no significant differences in preoperative characteristics, such as age, sex distribution, cataract grade, CDVA, higher-order aberrations, IOL power, or target refraction between the two groups. At 1 month postoperatively, CDVA, uncorrected distance, intermediate, and near visual acuity, higher-order aberrations, and contrast sensitivity exhibited no significant differences between groups. Conclusions In this short-term analysis, the PureSee IOL demonstrated comparable efficacy and safety in cataract patients with stage 1 ERM to those with a normal retina.

Background: Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli is among the most important multidrug-resistant pathogens causing bloodstream infections (BSIs).Cefotaximase (CTX-M) enzymes are the most common and highly diverse ESBL family in E.coli. CTX-M-15 in group CTX-M-1 and CTX-M-14 in group CTX-M-9 are the most extensively disseminated enzymes. Multidrug-resistant E. coli strains complicate empirical therapy and increase healthcare burden globally and in Korea. We investigated the molecular epidemiology, sequence types (STs), and ESBL genotypes of E. coli bloodstream isolates in Korea and identified clinical risk factors for cefotaxime resistance. Methods: We collected all non-duplicated isolates of E. coli and related clinical information from patients with BSIs at eight sentinel hospitals in the Korean Global Antimicrobial Resistance Surveillance System (Kor-GLASS) collection network during 2017–2021. Duplicate isolates were removed to ensure representativeness of the data. Antimicrobial susceptibility was tested using disk diffusion tests, and multilocus sequence typing and betalactamase genotyping were performed. Results: Among 9,232 E. coli blood isolates, resistance rates to cefotaxime and ceftazidime were 36.4% and 11.4%, respectively. Among the clinical factors, age > 65 yrs (adjusted odds ratio [aOR], 1.36), hospital-origin infection (aOR, 2.55), and admission type (intensive care unit [ICU] vs. general ward; aOR, 1.34) were significant cefotaxime resistance risk factors. ST131 was the most prevalent among cefotaxime-resistant E. coli (64.8%, 2,180/3,363), followed by ST1193 (5.3%, N = 177), and ST69 (5.1%, N = 170).ST131, ST648, ST405, and ST410 cefotaxime-resistant E. coli isolates frequently harbored blaCTX-M-15, whereas ST1193 and ST68 showed a high proportion of blaCTX-M-27 carriers, and most ST457 and ST5150 isolates carried blaCTX-M-55. Conclusions Continuous monitoring of ESBL-producing E. coli is required to prevent further dissemination, guide empirical therapy, inform infection control policies, and ensure early detection of multidrug-resistant clones with the potential for widespread transmission.

Purpose: Patient-derived cells (PDCs) and patient-derived organoids (PDOs) are complementary preclinical models widely used in translational cancer research. However, their molecular and functional differences have not been systematically characterized. This study established and analyzed paired PDC and PDO models derived from the same gastric cancer ascites to delineate platform-dependent molecular and functional profiles. Materials and Methods: Malignant ascites or pleural fluid obtained from 6 patients with advanced gastric cancer were used to establish paired PDC and PDO models. All pairs underwent comprehensive multi-omics profiling, integrating genomic, transcriptomic, and proteomic data. Phenotypic characterization included morphological, histological, proliferative, and cell cycle analyses. Drug sensitivity assays were performed using 4 chemotherapeutic agents commonly used to treat gastric cancer. Results: The 6 paired PDC and PDO models exhibited distinct morphological characteristics.Whole-genome analyses demonstrated high concordance among primary tumors, PDCs, and PDOs, confirming tumor representation across platforms. Multi-omics profiling identified platform-dependent molecular signatures; PDOs were enriched for extracellular matrix remodeling and stemness, whereas PDCs displayed proliferation- and immune-related signatures. Clinically relevant biomarkers, including HER2 and MET alterations, were concordant with primary tumors. Notably, drug responses differed between platforms and patients, indicating platform-dependent and patient-specific chemosensitivity. Conclusions Paired PDC and PDO models derived from the same patients preserved core patient-specific tumor characteristics while exhibiting distinct molecular and functional profiles. These findings underscore the culture platform as a critical determinant of experimental outcomes and therapeutic responses. Therefore, careful selection of an appropriate preclinical model is essential to accurately address biological questions and optimize precision oncology strategies.

The Pheochromocytoma of the Adrenal Gland Scaled Score (PASS) is widely used for risk stratification in pheochromocytoma and paraganglioma (PPGL), but its clinical utility is limited by inter-observer variability of its parameters and inconsistent predictive performance. Methods: We conducted a multicenter retrospective study of 1,518 patients with PPGL from five tertiary referral centers in Korea. Prognostic utility of PASS system was assessed using logistic regression, Kaplan-Meier analysis, and receiver operating characteristic (ROC) curve analysis. Inter-observer variability was inferred by comparing area under the ROC curve (AUCs) across institutions. Simplified PASS systems were developed based on multivariable analysis of key histopathological parameters. Results: The PASS system was a significant predictor of adverse events and recurrence-free survival. Although the PASS system demonstrated only modest discriminative ability (AUC, 0.673), it showed a high negative predictive value (NPV, 0.885), supporting its usefulness as a screening tool for benign behavior. However, there was significant inter-institutional variability in PASS performance (AUC; range, 0.513 to 0.727; p < .05). The 3-factor Simple PASS, which incorporates necrosis, spindling, and mitotic figures, exhibited less inter-observer variation. The 4-factor Simple PASS, which adds vascular invasion to the 3-factor model, also showed reduced inter-observer variability and improved AUC and NPV compared to the original PASS system. Conclusions: In this multicenter cohort, the PASS system demonstrated high NPV and screening potential, but significant inter-observer variability remains a challenge. Simplification of the PASS system and enhanced pathologist training may improve reproducibility and clinical utility in PPGL risk stratification.

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: Atherosclerotic plaques in peripheral arterial disease (PAD) include fatty, mixed, and calcified types. Plaque burden is significantly associated with restenosis, reintervention, and amputation-free survival. Rotational and aspirational atherectomy (RAA) may effectively remove such plaques. This study aimed to evaluate long-term outcomes of RAA for infrainguinal PAD. Methods: Patients with infrainguinal lesions underwent revascularization using the Jetstream Atherectomy System (Boston Scientific). This 60-month extension assessed primary patency rate (PPR) and clinically driven target lesion revascularization (CD-TLR). Kaplan-Meier curves were used for survival analysis; P < 0.05 was considered statistically significant. Results: A total of 150 patients (mean age, 70.9 years; male, 86.0%; 65.4% with diabetes) were enrolled. The mean lesion length was 15.8 cm, with 74.0% occlusions and 47.3% severe calcification. Lesions were sclerotic (72.4%), thrombosclerotic (13.4%), thrombotic (9.4%), or in-stent (4.7%). A drug-coated balloon (DCB) was used in 85.5% of cases. PPR at 1, 3, and 5 years was 84.1%, 68.1%, and 58.5%, respectively. CD-TLR rates were 93.0%, 81.5%, and 67.4%, respectively. The benefit of DCB was sustained through 3 years but attenuated thereafter, highlighting the need for extended follow-up in infrainguinal interventions. Conclusion RAA demonstrated durable 5-year patency and safety outcomes. Device type, DCB use, lesion morphology, and calcium grade did not significantly influence long-term results. Lesion complexity remains the primary predictor of clinical outcome. Despite the complexity of infrainguinal lesions, the use of RAA demonstrated sustained patency through 3 years, with lesion complexity (particularly TASC classification) emerging as the most critical predictor of long-term success.