Radiation-induced cavernous malformations (RICMs) are rare but significant late complications of highdose radiation therapy, particularly in young survivors of brain tumors. This report presents two cases of RICMs following aggressive multimodal treatment, including surgery, chemotherapy, and radiation therapy. Case 1 was a 22-year-old male patient with medulloblastoma treated with craniospinal irradiation, tumor bed boost, and tandem autologous peripheral blood stem cell transplantation. Approximately 8 years after treatment completion, routine follow-up imaging revealed a small focal hemorrhage in the right cerebellum, consistent with an RICM. The lesion was asymptomatic and managed conservatively with regular imaging, showing spontaneous resolution over time, with a significant size reduction noted 9 years post-treatment. Case 2 describes a 32-year-old male with an intracranial germinoma treated with whole-ventricular irradiation. Three years after treatment, the patient developed a symptomatic hemorrhagic RICM near a pre-existing developmental venous anomaly. Surgical resection and Gamma Knife Surgery stabilized the lesion; however, residual symptoms, including tremors and gait disturbances, persisted, affecting the patient’s daily activities. These cases illustrate the diverse clinical courses of RICMs, ranging from spontaneous resolution to the necessity of surgical intervention, and emphasize the importance of long-term surveillance and tailored management strategies for late-onset complications.

Background: This study analyzed the epidemiology and treatment outcomes of germ cell tumorpatients at a single institution. Methods: A retrospective analysis was conducted on intracranial germ cell tumor (iGCT) pa-tients treated at a single tertiary hospital from 2004 to 2019. Patients were categorized based on treatment modality: Korean Society for Pediatric Neuro-Oncology (KSPNO) protocol or bleomycin, etoposide, and cisplatin with radiation therapy. Results: Forty-nine iGCT patients treated with combined chemotherapy and radiotherapywere analyzed. The median age was 19 years (range: 6–40), with a median follow-up duration of 148.0 months (range: 10.5–265.5). Tumors were most common in the pineal gland (51.0%). Although no significant differences in outcomes were observed between treatment modalities, outcomes varied significantly by pathological type. The 10-year progression-free survival rates for germinoma and non-germinomatous germ cell tumors (NGGCTs) were 88.1% and 32.7%, respectively (p=0.003), while the 10-year overall survival rates were 92.9% and 67.5%, respectively (p<0.001). Fourteen patients experienced CTCAE (Common Terminology Criteria for Adverse Events) grade ≥3 adverse events, with one eventrelated death. Conclusion Pure germinoma demonstrated higher survival and lower recurrence rates comparedto NGGCT. The KSPNO protocol appears to be an acceptable and safe treatment option for iGCT patients. Further multi-institutional studies with larger cohorts are warranted.

Purpose: Thrombosis and bleeding significantly affect morbidity and mortality in myeloproliferative neoplasms (MPNs). The efficacy and safety of direct oral anticoagulants (DOACs) in MPN patients remain uncertain. Materials and Methods: We conducted a large, retrospective, nationwide cohort study using the Korean Health Insurance Review and Assessment Service database from 2010 to 2021. Results: Out of the 368 MPN patients included in the final analysis, 62.8% were treated with DOACs for atrial fibrillation (AF), and 37.2% for venous thromboembolism (VTE). The AF group was statistically older with higher CHA2DS2-VASc (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke, transient ischemic attack, or thromboembolism, vascular disease, age 65-74 years, sex category [female]) scores compared to the VTE group. Antiplatelet agents were used in 51.1% of cases, and cytoreductive drugs in 79.3%, with hydroxyurea being the most common (64.9%). The median follow-up was 22.3 months, with 1-year cumulative incidence rates of thrombosis and bleeding at 11.1% and 3.7%, respectively. Multivariate analysis identified CHA2DS2-VASc scores ≥ 3 (hazard ratio [HR], 3.48), concomitant antiplatelet use (HR, 2.57), and cytoreduction (HR, 2.20) as significant thrombosis risk factors but found no significant predictors for major bleeding. Conclusion Despite the limitations of retrospective data, DOAC treatment in MPN patients seems effective and has an acceptable bleeding risk.

Purpose: This study aimed to investigate whether levetiracetam (LEV), the most used antiepileptic drug, influences survival in patients with glioblastoma (GBM), using a national database. Materials and Methods: This study used data from the Korea Health Insurance Review and Assessment database. Patients diagnosed with GBM between 2007-2018 treated with standard therapy were included. The study population was divided into long-term (≥ 60 days) and short-term (< 30 days) LEV groups. A separate long-term valproic acid (VPA) group (≥ 60 days) was identified for comparison. Demographics, disease characteristics, and treatment parameters were collected. Kaplan-Meier method and Cox regression were used to compare survival outcomes between the groups. Results: Overall, 2,971 patients were included, with 1,319 and 1,652 in the short-term and long-term LEV groups, respectively. The median overall survival (OS) for the entire population was 19.15 months post-surgery. Kaplan-Meier analysis revealed a significantly longer median OS in the long-term LEV group versus the short-term LEV group. After adjusting for confounders, Cox proportional hazard analysis revealed an association of long-term LEV use with improved survival, which was also observed in a subgroup analysis of patients without preoperative seizure history. The long-term LEV group demonstrated longer median OS, compared with the long-term VPA group. Conclusion Our nationwide population-based study found an association between long-term LEV use and improved survival in patients with GBM, regardless of preoperative seizure history. Prospective studies are needed to validate these findings and investigate the potential impact of LEV on the survival outcomes of patients with GBM.

Purpose: Some studies suggest that TP53 mutations are associated with the response to immune checkpoint inhibitors (ICI) in patients with non–small cell lung cancer (NSCLC) and also contribute to sex disparities in several cancers. Thus, we hypothesized that TP53 mutations might serve as sex-dependent genomic biomarkers of ICI treatment response in patients with NSCLC. Materials and Methods: Clinical data of 100 patients with metastatic NSCLC treated with ICI monotherapy at Seoul National University Bundang Hospital (SNUBH) were retrospectively reviewed. Genomic and clinical datasets of The Cancer Genome Atlas and an ICI-treated lung cancer cohort (cBioPortal) were also analyzed. Results: In SNUBH cohort, no statistically significant difference was observed in the median progression-free survival (PFS) according to TP53 mutation status (p=0.930); however, female patients with TP53 mutations (MT) had a significantly prolonged median PFS compared to wild-type (WT) (6.1 months in TP53 MT vs. 2.6 months in TP53 WT; p=0.021). Programmed death-ligand 1 (PD-L1) high (≥ 50%) expression was significantly enriched in female patients with TP53 MT (p=0.005). The analysis from publicly available dataset also revealed that females with NSCLC with TP53 MT showed significantly longer PFS than those with TP53 WT (p < 0.001). In The Cancer Genome Atlas analysis, expression of immune-related genes, and tumor mutation burden score in TP53 MT females were higher than in males without TP53 MT. Conclusion Female patients with NSCLC with TP53 mutations had high PD-L1 expression and showed favorable clinical outcomes following ICI therapy, suggesting a need for further research to explore the role of TP53 mutations for sex disparities in response to ICI therapy.

Purpose: The metabolism of tamoxifen is influenced by various cytochrome p450 enzymes, including CYP2D6 and CYP2C19, leading to variations in the levels of endoxifen, even with the same tamoxifen dose. However, the clinical significance of endoxifen for the prognosis of breast cancer patients remains controversial. This study aimed to elucidate the relevance of endoxifen level to recurrence-free survival censored with tamoxifen discontinuation (RFSt), representing the RFS for tamoxifen itself, of breast cancer patients and determine a suitable cutoff for prognostication. Materials and Methods: The study included 478 breast cancer patients. Tamoxifen and its metabolites, including endoxifen, were measured using liquid chromatography-tandem mass spectrometry. An optimal cutoff was determined with maximally selected rank statistics. Survival analysis and Cox regression were conducted based on this cutoff. Results: An endoxifen level of 21.00 ng/mL was the optimal cutoff for prognostication. Survival analysis revealed a statistically significant difference in RFSt between the low endoxifen group (≤ 21.00 ng/mL) and the high endoxifen group (> 21.00 ng/mL) (log-rank test, p=0.032). The 10-year probability of RFSt was 83.2% (95% confidence interval [CI], 77.0 to 89.9) and 88.3% (95% CI, 83.3 to 93.5) in the low and high endoxifen groups, respectively. Multivariable Cox proportional hazards regression indicated endoxifen concentration as a significant factor associated with prognosis. Conclusion Endoxifen could serve as a marker for appropriate tamoxifen treatment with a cutoff of 21.00 ng/mL. Based on this cutoff, therapeutic drug monitoring would benefit patients displaying suboptimal endoxifen concentrations.

Genetic kidney diseases are caused by mutations in specific genes that significantly affect kidney development and function. Although the underlying pathogenic genes of many kidney diseases have been identified, an understanding of their mechanisms and effective treatments remains limited. Gene editing, particularly using clustered regularly interspaced short palindromic repeats (CRISPR), has recently become a promising approach for studying genetic diseases and the CRISPR/CRISPR-associated protein 9 (CRISPR-Cas9) method has become a prominent research method. It has been shown that CRISPR-Cas9 can be targeted to knock out specific genomic sites, which enables researchers to correct gene mutations, prevent inheritance, and better understand the function of genes and the effectiveness of drugs. However, the application of CRISPR-Cas9 technology in the development of therapeutic agents against genetic kidney disease has been overlooked compared with other genetic diseases. In this paper, we provide an overview of the current research advancements in genetic kidney diseases using CRISPR technology, as well as the diverse preclinical research methods implemented, with particular emphasis on autosomal dominant polycystic kidney disease.

Background/Aims: A clinical unmet need persists for medications capable of modulating the progression of primary sclerosing cholangitis (PSC). This study aimed to assess the clinical feasibility of HK-660S (beta-lapachone) in PSC. Methods: In this multicenter, randomized, double-blind, placebo-controlled, parallel-group phase 2 trial, participants were assigned in a 2:1 ratio to receive either 100 mg of HK-660S or a placebo twice daily for 12 weeks. The primary outcomes were the reduction in serum alkaline phosphatase (ALP) levels and the percentage of participants showing improvements in PSC severity, as determined by magnetic resonance cholangiopancreatography with the Anali score. Secondary endpoints included changes in liver stiffness and adverse events. Results: The analysis included 21 patients, 15 receiving HK-660S, and six receiving a placebo. Improvements in the Anali score were observed in 13.3% of the HK-660S group, with no improvements in the placebo group. HK-660S treatment resulted in a 15.2% reduction in mean ALP levels, compared to a 6.6% reduction in the placebo group. A stratified ad-hoc analysis based on baseline ALP levels showed a statistically significant response in the HK-660S group among those with ALP levels greater than twice the upper limit of normal, with a 50% responder rate (p=0.05). Additionally, 26.7% of the HK-660S group showed improvements in the enhanced liver fibrosis score, with no improvements in the placebo group. HK-660S was generally well tolerated. Conclusions HK-660S is well tolerated among patients with PSC and may improve bile duct strictures, decrease serum ALP levels, and reduce liver fibrosis (cris.nih.go.kr, Number KCT0006590).

Colonoscopy, a widely used procedure for diagnosing and treating colonic diseases, induces transient gastrointestinal symptoms and alterations in the gut microbiota. This review comprehensively examines the evidence on alterations in the gut microbiota following colonoscopy and their possible mechanisms. Factors such as rapid colonic evacuation, increased osmolality, and mucus thinning caused by bowel preparation and exposure to oxygen during the procedure contribute to these alterations. Typically, the alterations revert to the baseline within a short time. However, their long-term implications remain unclear, necessitating further investigation. Split-dose bowel preparation and CO2 insufflation during the procedure result in fewer alterations in the gut microbiota. Probiotic administration immediately after colonoscopy shows promise in reducing alterations and gastrointestinal symptoms. However, the widespread use of probiotics remains controversial due to the transient nature of both the symptoms and gut microbial alterations following a colonoscopy. Probiotics may offer greater benefits to individuals with preexisting gastrointestinal symptoms. Thus, probiotic administration may be a viable option for selected patients.