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: Clopidogrel requires several hours to achieve adequate platelet inhibition. We investigated the association of clopidogrel preloading time with 30-day clinical outcomes and post-procedural troponin elevation in patients with stable angina undergoing elective percutaneous coronary intervention (PCI). Methods: This single-center retrospective cohort study included 1,020 patients with stable angina (clopidogrel-naive) who received 300 mg clopidogrel preloading within 24 hours before elective PCI between 2012 and 2020. Patients were categorized according to clopidogrel preloading-to-balloon time ≤6 hours or >6 hours. The primary endpoint was 30-day major adverse cardiovascular events (MACE), defined as a composite of all-cause death, myocardial infarction, stroke, and any revascularization. Secondary endpoints included serial troponin T changes and troponin T elevation ≥5×, ≥25×, and ≥70× the upper reference limit. Stabilized inverse probability of treatment weighting (IPTW) was used. Results: Thirty-day MACE occurred in five patients (0.49%) and did not differ between the ≤6-hour and >6-hour groups after IPTW (0.5% vs. 0.4%, p=0.754). Post-procedural troponin T levels at 6, 24, and 48 hours were higher in the ≤6-hour group. Patients with shorter preloading-to-balloon times showed higher peak troponin T levels, with the greatest difference at the ≤1-hour cutoff (geometric mean ratio, 2.12; 95% confidence interval, 1.53–2.95; p<0.001) and progressive attenuation at longer cutoffs. Troponin T elevation ≥5× and ≥25× was more frequent in the ≤6-hour group, whereas ≥70× elevation did not differ. Conclusion Clopidogrel preloading ≤6 hours before elective PCI was not associated with increased 30-day MACE but was associated with lower-threshold post-procedural troponin T elevation.

Background: Dual antiplatelet therapy with aspirin and a P2Y12 inhibitor is standard after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS); however, bleeding risk remains a major concern. Early discontinuation of aspirin due to potent P2Y12 inhibition may mitigate bleeding without increasing thrombotic events. Methods: The ASpirin-FREE therapy after successful percutaneous coronary intervention for acute coronary syndrome (ASFREE) study was an investigator-initiated, single-center, prospective, open-label, single-arm pilot study enrolling patients with ACS who underwent PCI with drug-eluting stents. All patients received a single loading dose of aspirin on the day of the PCI, followed by ticagrelor or prasugrel monotherapy. The primary efficacy endpoint was target vessel failure (TVF) at 12 months. The primary safety endpoint was definite stent thrombosis. Event rates are reported with 95% confidence intervals (CIs). Results: In total, 228 patients were enrolled. TVF occurred in 10 patients (4.4%; 95% CI, 2.1%–7.9%). Definite stent thrombosis was observed in one patient (0.4%; 95% CI, 0.01%–2.4%), with no acute or subacute events. Major bleeding (Bleeding Academic Research Consortium type 3 or 5) occurred in two patients (0.9%; 95% CI, 0.1%–3.1%). Conclusion An aspirin-free strategy following a single loading dose with continuation of potent P2Y12 inhibitor monotherapy was feasible in patients with ACS undergoing PCI and was associated with low rates of thrombotic and major bleeding events. These findings should be regarded as hypothesis-generating and supporting further evaluations in adequately powered randomized controlled trials (CRIS registration: KCT0008182).

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.

Objective: This study aimed to evaluate reproductive outcomes according to the timing of testicular sperm retrieval. Methods: The study included 282 infertile couples divided into three groups: group A (freeze-thawed testicular sperm extraction [TESE] sperm, n=233), group B (fresh TESE sperm collected 1 day before ovum pickup, n=22), and group C (fresh TESE sperm collected on the same day as ovum pickup, n=27). The indications for TESE were surgically uncorrectable azoospermia or ejaculation failure, often accompanied by medical comorbidities such as diabetes mellitus and spinal cord injury. The outcome parameters assessed were fertilization rates, embryo quality, and clinical pregnancy rates. Results: The mean paternal age was 36.8±5.7 years, and the mean maternal age was 32.6±3.5 years. The mean duration of infertility was 2.9±1.8 years. The fertilization rates were 70.7%, 78.9%, and 73.0% for groups A, B, and C, respectively (p=0.047). The percentages of good-quality embryos were 68.2%, 65.3%, and 48.4%, respectively (p=0.007); specifically, the percentage of good-quality embryos was significantly lower in group C compared with the other two groups. Clinical pregnancy rates per transfer were similar at 51.1%, 50.0%, and 48.1% (p=0.958), with no differences observed in miscarriage rates. Conclusion Testicular sperm retrieval can be safely performed 1 day before ovum pickup, resulting in favorable fertility outcomes.

Background: The conventional magnetic resonance imaging (MRI) grading system for foraminal stenosis (FS), known as the Lee classification, was introduced in 2010 and is widely utilized in clinical practice. Previous studies have reported that the conventional grading system for FS lacks prediction ability for surgical treatment. The purpose of this study was to develop a novel MRI grading system for lumbar FS with improved prediction ability for surgical treatment by incorporating facet effusion to indicate segmental instability. Methods: We retrospectively reviewed patients diagnosed with lumbar FS between 2011 and 2017 who had a follow-up period of at least 5 years. The FS severity was assessed using a conventional MRI grading system developed by Lee et al. We recorded whether the patient underwent surgical treatment for FS during the follow-up period and the time from the initial diagnosis to surgery. Survival analysis using a Kaplan-Meier curve and log-rank test was performed to verify the impact of FS severity on the surgical treatment. We performed additional survival analysis after modifying the grading system by incorporating the presence of excessive facet joint effusion assessed using axial MRI. We also compared the discrimination ability of the modified and conventional grading systems using Uno’s concordance index (C-index). Results: In total, 235 patients with a mean age of 63.7 years were included in this study. During the mean follow-up period of 8.1 years, 63 patients underwent surgical treatment for FS. The conventional grading system revealed no significant difference in survival between the grade 2 and 3 groups (p = 0.104). Conversely, the modified grading system revealed a significant difference in survival between the new grade 2 and 3 groups (p < 0.001). After modification, the discrimination ability, assessed using Uno’s Cindex, significantly improved from 0.69 to 0.73. Conclusions The Facet Effusion-Incorporating Grading System, which adds excessive facet joint effusion to the conventional MRI grading framework, demonstrated improved predictive value for surgical treatment and better discriminatory ability compared with the original system.

Background: Degenerative lumbar scoliosis (DLS) alters spinal anatomy, impacting the feasibility and dimensions of surgical corridors for oblique lumbar interbody fusion (OLIF). This study aimed to compare the morphometric characteristics of OLIF corridors between patients with left- and right-apex curves, focusing on corridor dimensions, psoas muscle asymmetry, and segmental artery positioning. Methods: A retrospective analysis of 80 patients with DLS (left apex: n = 43; right apex: n = 37) was conducted. Corridor angles and distances, psoas muscle cross-sectional areas, and segmental artery locations were measured at L2–3, L3–4, and L4–5 using T2-weighted magnetic resonance imaging (MRI). Multivariate regression analysis identified key anatomical predictors of corridor variation at L2–3. Results: Regardless of the apex direction, the left-sided corridor was consistently larger across all levels. Corridor angles were significantly greater on the left side in both groups (left apex: L2–3, 39.7° vs. 13.5°; L3–4, 38.3° vs. 11.9°; L4–5, 38.6° vs. 6.9°;right apex: L2–3, 53.7° vs. 18.1°; L3–4, 43.1° vs. 18.5°; L4–5, 28.6° vs. 11.9°). Psoas muscle areas were larger on the concave side of the curve (left apex: 125.7 mm2 vs. 67.9 mm2 ; right apex: 125.4 mm2 vs. 77.4 mm2 ). Segmental artery positioning exhibited curvedependent asymmetry at L2–3 (left apex: 8.8 mm vs. 7.9 mm; right apex: 9.6 mm vs. 8.0 mm). Multivariate regression analysis revealed that in the left apex group, the left psoas area (β = −0.132) and segmental artery distances were significant predictors of corridor angle variation (R2 = 0.517). In the right apex group, psoas asymmetry (β = 0.123) and sagittal alignment (β = −0.851) were associated with corridor differences. Conclusions OLIF corridors in DLS patients demonstrate consistent left-sided dominance, regardless of apex direction. Psoas muscle asymmetry and segmental artery positioning contribute to corridor variations. While the left-sided approach remains standard, right-sided access may be feasible in select cases, particularly at L4–5. These findings provide insights for optimizing preoperative planning and surgical decision-making in DLS patients.

Background: and Purpose: Clinicians typically use 2 methods to determine impairment in a specific cognitive domain based on the Seoul Neuropsychological Screening Battery, 2nd Edition: (1) identifying impairment when one or more subtests fall below the normal range (< mean −1.5 standard deviation), and (2) using the cognitive domain score. Because agreement between these methods may differ by the severity of cognitive impairment, this study examined their concordance in the overall sample and across Clinical Dementia Rating (CDR) levels. Methods: A total of 1,086 patients (age 74.27±9.62 years; education 9.07±4.77 years) were included. Concordance between subtest-based and domain score-based classifications was assessed for each cognitive domain using cross-tabulation analyses and Cohen’s kappa statistics. To assess the influence of the severity of cognitive impairment, analyses were conducted across CDR levels. Results: When impairment was defined as having at least one abnormal subtest, concordance rates were 90.8% for Attention, 88.8% for Language, 84.6% for Visuospatial Function, 74.3% for Memory, and 73.6% for Frontal/Executive Function. In the Frontal/ Executive Function domain, requiring 2 or more abnormal subtests increased concordance to 90.9%. CDR subgroup analyses showed that Memory concordance was particularly low in the CDR 0.5 group (65.8%) compared with the CDR 1 (85.5%) and CDR 2 (98.5%) groups. Conclusions Concordance between the 2 classification methods was moderately high for Attention, Language, and Visuospatial Function but substantially lower for Memory and Frontal/Executive Function, especially in individuals with mild cognitive impairment. These findings highlight the need to consider both subtest-level performance and domain scores when determining impairment in memory or frontal/executive function.

Background: and Purpose: To assess the long-term effectiveness, safety, and economic viability of recently approved Alzheimer’s disease (AD) therapies, as well as to evaluate the real-world application of novel diagnostics among AD patients with diverse comorbidities, comprehensive real-world data (RWD) analysis is essential. The Korean JOint RegistrY for ALZheimer’s Treatment and Diagnostics (JOY-ALZ) endeavors to create a registry of RWD derived from clinical practice on new diagnostic methods and therapeutic agents for AD introduced in Korea since 2021. Methods: Participants must fulfill all the following: 1) be at least 19 years old; 2) be actively receiving, scheduled to initiate, or undergoing evaluation for any AD disease-modifying treatment; 3) have completed amyloid positron emission tomography or cerebrospinal fluid AD immunoassay (a positive result is not essential for participation); 4) have a clinical classification of cognitively unimpaired, mild cognitive impairment, or probable AD dementia. Data generated during routine care is segmented into a minimum dataset, extended dataset, and research-only dataset requiring extra consent. Assessments encompass clinical, cognitive, functional, neurobehavioral, neuroimaging, and biomarker evaluations, in addition to systematic monitoring of new AD treatments and their safety.Data are collected and monitored at baseline, at semiannual intervals during the initial 2 years, and then annually up to 2034. To date, 46 medical centers will participate in JOY-ALZ. Conclusions JOY-ALZ is expected to promote understanding of the long-term clinical outcomes, safety, and cost-effectiveness of recently introduced diagnostics and treatments for AD, thereby supporting the progress of precision medicine in AD care and diagnosis.

Background: and Purpose To compare the epidemiological and clinical features of the rare patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) with age- and sex-matched controls in a nationwide cohort from South Korea. Methods: This observational cohort study analyzed newly diagnosed CADASIL patients aged at least 20 years and matched controls using data from the National Health Information Database for 2004–2022. The cumulative incidence of CADASIL was assessed by age and sex, and compared between regions. Neurologic and systemic diseases were compared between the CADASIL and control groups. Results: The study analyzed 816 CADASIL patients and 816 age- and sex-matched controls aged 56.8±15.2 years (mean±standard deviation), among whom 48.3% were male. The cumulative incidence of CADASIL was 1.86 per 100,000 people (95% confidence interval [CI]=1.85– 1.87 per 100,000), and peaked at 60–69 years of age. In terms of regional distribution, the incidence was highest for Jeju, at 39.67 per 100,000 (95% CI 37.84–41.49 per 100,000). Neurologic diseases were more frequent in CADASIL patients, including Alzheimer’s disease (33.1% vs.20.0%), vascular dementia (84.9% vs. 5.0%), epilepsy (34.6% vs. 15.9%), stroke (70.7% vs. 27.6%), parkinsonism (18.9% vs. 11.0%), and depression (60.8% vs. 44.9%). Systemic diseases such as diabetes mellitus (78.9% vs. 68.9%) were also more common in CADASIL patients, while cancer (27.9% vs. 38.7%) and myocardial infarction (10.0% vs. 13.6%) were less common than in controls. The onset ages of all diseases were lower in CADASIL patients. Conclusions This study has provided a precise nationwide estimate of the CADASIL incidence and its regional distribution in South Korea. CADASIL patients showed higher incidence rates and earlier onsets of diverse clinical manifestations.