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: The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome has been proposed to be a downstream mediator of neuroinflammation in individuals with Parkinson’s disease (PD). However, its involvement across disease stages and related synucleinopathies, such as multiple system atrophy (MSA), remains unclear. We aimed to analyze the peripheral mRNA expression of NLRP3-related genes and cytokines across individuals with isolated REM sleep behavior disorder (iRBD), early-stage PD, late-stage PD, and MSA. Methods: Peripheral blood mononuclear cells (PBMCs) were collected from 151 participants: 35 healthy controls (HCs), 31 patients with iRBD, 41 patients with early-stage PD, 21 patients with late-stage PD, and 23 patients with MSA. mRNA expression was measured using quantitative real-time polymerase chain reaction. Statistical comparisons were performed using analysis of variance (ANOVA) or Welch’s ANOVA, and associations with clinical variables were analyzed through stepwise multiple linear regression. Results: NLRP3 expression was significantly lower in patients with iRBD (p=0.0263) and patients with early-stage PD (p= 0.0101) than in HCs. NIMA-related kinase 7 (NEK7) expression progressively decreased across the disease spectrum (HCs vs. patients with early-stage PD, p=0.0008; vs. patients with late-stage PD, p<0.0001). In contrast, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and caspase-1 were elevated in patients with PD, especially those in the late stages. Levels of patients with MSA resembled those of HCs but differed from those of patients with PD. Interleukin (IL)-1β and IL-18 levels were not significantly different. In patients with early-stage PD, NLRP3 expression was negatively correlated with disease duration, the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale Part II score, and the cognitive score. Conclusion Our findings challenge the prevailing hypothesis that NLRP3 inflammasome activation directly contributes to PD pathogenesis. Instead, the observed increase in ASC and caspase-1 expression suggests the potential involvement of alternative inflammasome pathways during disease progression.

Background: Multiple perinatal factors influence hemodynamically significant patent ductus arteriosus (HS PDA) in preterm infants.Purpose: This study aimed to identify the risk factors associated with HS PDA in very low birth weight infants (VLBWIs) and determine the predictors of surgical ligation. Methods: This retrospective study included VLBWIs born at 23–32 weeks’ gestation whose HS PDA properties could be identified using echocardiography. The infants were stratified into 2 groups based on gestational age (23–27 and 28–32 weeks). Results: Among the 496 included VLBWIs, 171 had no PDA, 90 had non-HS PDA, and 235 had HS PDA. In infants born at 23–27 weeks’ gestation, risk factors for HS PDA included low birth weight, the absence of histological chorioamnionitis, and premature rupture of membranes. For VLBWIs born at 28–32 weeks’ gestation, HS PDA was associated with lower birth weight, frequent surfactant treatment, and maternal hypertension. Within the HS PDA group, infants with a lower birth weight or who received incomplete antenatal steroid administration had an increased likelihood of requiring surgical ligation, whereas those with a small-for-gestational-age status had a decreased need for surgical ligation. Conclusion Recognizing these risk factors can aid the development of targeted treatment strategies for HS PDA in VLBWIs, enabling early ligation and potentially reducing the need for surgical management.

Background and Objectives: Primary prevention (PP) implantable cardioverter-defibrillator (ICD) therapy for ischemic cardiomyopathy (ICM) is underused in Asian countries, including South Korea. Both clinical and hospital factors may influence appropriate ICD use. We evaluated whether determinants of PP ICD implantation differ by hospital implantation volume. Methods: In this prospective, multicenter observational registry (blinded for review), patients eligible for PP ICD were enrolled. Factors associated with ICD implantation—clinical characteristics and hospital-level systems—were examined across 4 large-volume hospitals (≥ 15 implants during the study) and 12 small-volume hospitals (< 15). Multivariable logistic regression identified independent predictors. Results: Among 3,083 ICM patients (2,403 men; median age 70 years), PP ICD implantation rates were 10.8% in large-volume and 5.7% in small-volume hospitals. Across groups, male sex and chronic kidney disease independently predicted ICD implantation. Regarding hospital factors, non-monetary incentives for referral were the sole independent predictor in large-volume centers (odds ratio [OR], 3.55; 95% confidence interval [CI], 2.07–6.10;P < 0.001). In small-volume centers, heart failure conferences (OR, 12.73; 95% CI, 1.72–94.37;P = 0.013), structured education systems (OR, 11.72; 95% CI, 2.45–56.12; P = 0.02), and pacemaker clinics (OR, 11.4; 95% CI, 2.24–58.39; P = 0.003) were independently associated with implantation. Conclusions Clinical predictors of PP ICD use were consistent across hospital volumes, but hospital-level determinants differed. Referral incentives characterized large-volume centers, whereas conferences, education systems, and pacemaker clinics were key in smallvolume centers. Tailored institutional strategies by hospital volume may help close the PP ICD underuse gap and improve evidence-based implementation.

Purpose: Based on the KEYNOTE-522 study, neoadjuvant pembrolizumab plus chemotherapy has become the standard treatment for early-stage triple-negative breast cancer (TNBC).This study evaluated the real-world efficacy, safety, and predictors of pathologic complete response (pCR) in Korean patients. Methods: We conducted a retrospective cohort study of 174 patients with early-stage TNBC who received the KEYNOTE-522 regimen (neoadjuvant pembrolizumab plus paclitaxel and carboplatin, followed by doxorubicin and cyclophosphamide) at a tertiary cancer center between August 2022 and July 2024. We assessed the primary endpoints, including pCR rate and event-free survival (EFS). We performed univariable and multivariable logistic regression analyses to identify independent predictors of pCR. Results: The median patient age was 50 years (range, 24–74 years). The clinical stages were II and III in 79.3% and 20.1% of patients, respectively, and 10.9% had clinical N3 disease. The overall pCR rate was 62.1%, and the N3 subgroup had a pCR rate of 47.4%. On multivariable analysis, high baseline Ki-67 expression (≥ median, 75%) was significantly associated with pCR (odds ratio, 2.84; 95% confidence interval, 1.45 to 5.66; p = 0.002). At a median followup of 18.4 months, the 12-month EFS rate was 97.4%, with significantly superior outcomes observed in patients who achieved pCR compared with those who did not achieve pCR (100% vs. 93.1%, p = 0.007). The treatment completion rate was 92.0%, and immune-related adverse events occurred in 13.8% of patients. Conclusion In this real-world analysis of one of the largest Asian cohorts of patients with earlystage TNBC treated with neoadjuvant pembrolizumab, the KEYNOTE-522 regimen demonstrated substantial efficacy and manageable toxicity, consistent with the original trial findings.

Background and Objectives: Cardiac resynchronization therapy (CRT) is a treatment option for patients with heart failure and left ventricular (LV) dyssynchrony. However, one-third of CRT patients are non-responders. The objective of this study is to evaluate the feasibility of an in silico electromechanical heart model to predict CRT outcomes. Methods: The three-dimensional heart geometries of 11 patients (age, 64.0 ± 10.7 years, 4 men) with CRT were constructed from cardiac computed tomography images. The finite element method was used to simulate the electrical wave propagation and mechanics in the heart. We coupled cardiac electrical excitation and mechanical contraction with vascular hemodynamics using a lumped parameter model. We predicted the LV end-diastolic and end-systolic volumes and LV ejection fraction (LVEF) after CRT implantation using the in silico CRT simulation model. A CRT responder was defined as a patient with an absolute LVEF increase ≥ 5%. We compared the in silico CRT outcomes with the real CRT outcomes. Results: Two patients were in silico CRT responders, and those 2 patients were also real CRT responders. Nine patients were in silico CRT non-responders, 8 who were real CRT non-responders, and 1 who was a real CRT responder. The in silico CRT outcomes agreed with the real CRT outcomes in 10 of 11 patients. The positive and negative predictive values, accuracy, sensitivity, and specificity of the in silico CRT model were 100%, 88.9%, 90.9%, 66.7%, and 100%, respectively. Conclusion The in silico CRT simulation model is feasible for predicting real CRT outcomes.

Purpose: In men with metastatic castration-resistant prostate cancer (mCRPC), new bone lesions are sometimes not properly categorized through a confirmatory bone scan, and clinical significance of the test itself remains unclear. This study aimed to demonstrate the performance rate of confirmatory bone scans in a real-world setting and their prognostic impact in enzalutamide-treated mCRPC. Materials and Methods: Patients who received oral enzalutamide for mCRPC during 2014-2017 at 14 tertiary centers in Korea were included. Patients lacking imaging assessment data or insufficient drug exposure were excluded. The primary outcome was overall survival (OS). Secondary outcomes included performance rate of confirmatory bone scans in a real-world setting. Kaplan-Meier analysis and multivariate Cox regression analysis were performed. Results: Overall, 520 patients with mCRPC were enrolled (240 [26.2%] chemotherapy-naïve and 280 [53.2%] after chemotherapy). Among 352 responders, 92 patients (26.1%) showed new bone lesions in their early bone scan. Confirmatory bone scan was performed in 41 patients (44.6%), and it was associated with prolonged OS in the entire population (median, 30.9 vs. 19.7 months; p < 0.001), as well as in the chemotherapy-naïve (median, 47.2 vs. 20.5 months; p=0.011) and post-chemotherapy sub-groups (median, 25.5 vs. 18.0 months; p=0.006). Multivariate Cox regression showed that confirmatory bone scan performance was an independent prognostic factor for OS (hazard ratio 0.35, 95% confidence interval, 0.18 to 0.69; p=0.002). Conclusion Confirmatory bone scan performance was associated with prolonged OS. Thus, the premature discontinuation of enzalutamide without confirmatory bone scans should be discouraged.

Objective: Fall from height (FFH) is a major public health problem that can result in severe injury, disability, and death. This study investigated how the characteristics of jumpers and fallers differ. Methods: This was a retrospective study of FFH patients enrolled in an Emergency Department-based Injury In-depth Surveillance (EDIIS) registry between 2011 and 2018. Depending on whether the injury was intentional, FFH patients who had fallen from a height of at least 1 m were divided into two groups: jumpers and fallers. Patient characteristics, organ damage, and death were compared between the two groups, and factors that significantly affected death were identified using multivariable logistic analysis. Results: Among 39,419 patients, 1,982 (5.0%) were jumpers. Of the jumpers, 977 (49.3%) were male, while 30,643 (81.9%) of fallers were male. The jumper group had the highest number of individuals in their 20s, with the number decreasing as age increased. In contrast, the number of individuals in the faller group rose until reaching their 50s, after which it declined. More thoracoabdominal, spinal, and brain injuries were found in jumpers. The in-hospital mortality of jumpers and fallers was 832 (42.0%) and 1,268 (3.4%), respectively. Intentionality was a predictor of in-hospital mortality, along with sex, age, and fall height, with an odds ratio of 7.895 (95% confidence interval, 6.746–9.240). Conclusion Jumpers and fallers have different epidemiological characteristics, and jumpers experienced a higher degree of injury and mortality than fallers. Differentiated prevention and treatment strategies are needed for jumpers and fallers to reduce mortality in FFH patients.

Background: Type 2 diabetes mellitus (T2DM) induces endothelial dysfunction and inflammation, which are the main factors for atherosclerosis and cardiovascular disease. The present study aimed to compare the effects of rosuvastatin monotherapy and rosuvastatin/ezetimibe combination therapy on lipid profile, insulin sensitivity, and vascular inflammatory response in patients with T2DM. Methods: A total of 101 patients with T2DM and dyslipidemia were randomized to either rosuvastatin monotherapy (5 mg/day, n=47) or rosuvastatin/ezetimibe combination therapy (5 mg/10 mg/day, n=45) and treated for 12 weeks. Serum lipids, glucose, insulin, soluble intercellular adhesion molecule-1 (sICAM-1), and peroxiredoxin 4 (PRDX4) levels were determined before and after 12 weeks of treatment. Results: The reduction in low density lipoprotein cholesterol (LDL-C) by more than 50% from baseline after treatment was more in the combination therapy group. The serum sICAM-1 levels increased significantly in both groups, but there was no difference between the two groups. The significant changes in homeostasis model assessment of insulin resistance (HOMA-IR) and PRDX4 were confirmed only in the subgroup in which LDL-C was reduced by 50% or more in the combination therapy group. However, after adjusting for diabetes mellitus duration and hypertension, the changes in HOMA-IR and PRDX4 were not significant between the two groups. Conclusion Although rosuvastatin/ezetimibe combination therapy had a greater LDL-C reduction effect than rosuvastatin monotherapy, it had no additional effects on insulin sensitivity and vascular inflammatory response. Further studies are needed on the effect of long-term treatment with ezetimibe on insulin sensitivity and vascular inflammatory response.

Background: Atherogenic dyslipidemia, which is frequently associated with type 2 diabetes (T2D) and insulin resistance, contributes to the development of vascular complications. Statin therapy is the primary approach to dyslipidemia management in T2D, however, the role of non-statin therapy remains unclear. Ezetimibe reduces cholesterol burden by inhibiting intestinal cholesterol absorption. Fibrates lower triglyceride levels and increase high-density lipoprotein cholesterol (HDL-C) levels via peroxisome proliferator- activated receptor alpha agonism. Therefore, when combined, these drugs effectively lower non-HDL-C levels. Despite this, few clinical trials have specifically targeted non-HDL-C, and the efficacy of triple combination therapies, including statins, ezetimibe, and fibrates, has yet to be determined. Methods: This is a multicenter, prospective, randomized, open-label, active-comparator controlled trial involving 3,958 eligible participants with T2D, cardiovascular risk factors, and elevated non-HDL-C (≥100 mg/dL). Participants, already on moderate-intensity statins, will be randomly assigned to either Ezefeno (ezetimibe/fenofibrate) addition or statin dose-escalation. The primary end point is the development of a composite of major adverse cardiovascular and diabetic microvascular events over 48 months. Conclusion This trial aims to assess whether combining statins, ezetimibe, and fenofibrate is as effective as, or possibly superior to, statin monotherapy intensification in lowering cardiovascular and microvascular disease risk for patients with T2D. This could propose a novel therapeutic approach for managing dyslipidemia in T2D.