Purpose: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. Materials and Methods: From January 2001 to December 2015, data of pediatric patients (0–18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. Results: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). Conclusion The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Background and Objectives: De-escalation of dual-antiplatelet therapy through dose reduction of prasugrel improved net adverse clinical events (NACEs) after acute coronary syndrome (ACS), mainly through the reduction of bleeding without an increase in ischemic outcomes. Whether the benefits of de-escalation are sustained in highly thrombotic conditions such as ST-elevation myocardial infarction (STEMI) is unknown. We aimed to assess the efficacy and safety of de-escalation therapy in patients with STEMI or non-STsegment elevation ACS (NSTE-ACS). Methods: This is a pre-specified subgroup analysis of the HOST-REDUCE-POLYTECH-ACS trial. ACS patients were randomized to prasugrel de-escalation (5 mg daily) or conventional dose (10 mg daily) at 1-month post-percutaneous coronary intervention. The primary endpoint was a NACE, defined as a composite of all-cause death, non-fatal myocardial infarction, stent thrombosis, clinically driven revascularization, stroke, and bleeding events of grade ≥2 Bleeding Academic Research Consortium (BARC) criteria at 1 year. Results: Among 2,338 patients included in the randomization, 326 patients were diagnosed with STEMI. In patients with NSTE-ACS, the risk of the primary endpoint was significantly reduced with de-escalation (hazard ratio [HR], 0.65; 95% confidence interval [CI], 0.48– 0.89; p=0.006 for de-escalation vs. conventional), mainly driven by a reduced bleeding. However, in those with STEMI, there was no difference in the occurrence of the primary outcome (HR, 1.04; 95% CI, 0.48–2.26; p=0.915; p for interaction=0.271). Conclusions Prasugrel dose de-escalation reduced the rate of NACE and bleeding, without increasing the rate of ischemic events in NSTE-ACS patients but not in STEMI patients.

Background: As the number of large-scale studies involving multiple organizations producing data has steadily increased, an integrated system for a common interoperable format is needed. In response to the coronavirus disease 2019 (COVID-19) pandemic, a number of global efforts are underway to develop vaccines and therapeutics. We are therefore observing an explosion in the proliferation of COVID-19 data, and interoperability is highly requested in multiple institutions participating simultaneously in COVID-19 pandemic research. Results: In this study, a laboratory information management system (LIMS) approach has been adopted to systemically manage various COVID-19 non-clinical trial data, including mortality, clinical signs, body weight, body temperature, organ weights, viral titer (viral replication and viral RNA), and multiorgan histopathology, from multiple institutions based on a web interface. The main aim of the implemented system is to integrate, standardize, and organize data collected from laboratories in multiple institutes for COVID-19 non-clinical efficacy testings. Six animal biosafety level 3 institutions proved the feasibility of our system. Substantial benefits were shown by maximizing collaborative high-quality non-clinical research. Conclusions This LIMS platform can be used for future outbreaks, leading to accelerated medical product development through the systematic management of extensive data from non-clinical animal studies.

Purpose: Ruptured abdominal aortic aneurysm (rAAA) is one of the most common aortic emergencies in vascular surgery and is associated with high operative mortality and morbidity rates despite recent treatment advances. We evaluated operative mortality risks for the outcomes of emergency endovascular aneurysm repair (eEVAR) vs. open repair in rAAA. Methods: Twenty patients underwent eEVAR (n = 12) or open repair (n = 8) for rAAA between 2016 and 2020. We adopted the EVAR first strategy since 2018. Primary endpoints included in-hospital mortality and 1-year survival. The outcome variables were analyzed with Fisher exact, Mann-Whitney test, and linear by linear association. The Kaplan-Meier method was used to estimate survival. Results: There were 13 males (65.0%) and the median age of the study cohort was 78.0 years (range, 49–88 years). Inhospital mortality occurred in 7 patients (35.0%); 5 (50.0%) in the early period and 2 (20.0%) in the later period of this series. According to the procedure type, 4 (50.0%) and 3 (25.0%) in-hospital mortalities occurred in the open repair and eEVAR patients, respectively. In 6 patients (50.0%), eEVAR was performed on unfavorable anatomy. The 1-year survival of eEVAR vs. open repair group was 75% ± 12.5% and 50% ± 17.7%, respectively. On univariate analysis, preoperative highrisk indices, postoperative acute renal failure requiring dialysis, pulmonary complications, and prolonged mechanical ventilation were associated with higher operative mortality. Conclusion The current data showed relatively superior outcomes with eEVAR vs. open repair for rAAA, even in some patients with unfavorable anatomy supporting the feasibility, efficacy, and safety of EVAR first strategy.

Objective: To compare the convenience and effectiveness of the existing lumbosacral orthoses (LSO) (classic LSO and Cybertech) and a newly developed LSO (V-LSO) by analyzing postoperative data. Methods: This prospective cohort study was performed from May 2019 to November 2019 and enrolled and analyzed 88 patients with degenerative lumbar spine disease scheduled for elective lumbar surgery. Three types of LSO that were provided according to the time of patient registration were applied for 6 weeks. Patients were randomized into the classic LSO group (n=31), Cybertech group (n=26), and V-LSO group (n=31). All patients were assessed using the Oswestry Disability Index (ODI) preoperatively and underwent plain lumbar radiography (anteroposterior and lateral views) 10 days postoperatively. Lumbar lordosis (LS angle) and frontal imbalance were measured with and without LSO. At the sixth postoperative week, a follow-up assessment with the ODI and orthosis questionnaire was conducted. Results: No significant differences were found among the three groups in terms of the LS angle, frontal imbalance, ODI, and orthosis questionnaire results. When the change in the LS angle and frontal imbalance toward the reference value was defined as a positive change with and without LSO, the rate of positive change was significantly different in the V-LSO group (LS angle: 41.94% vs. 61.54% vs. 83.87%; p=0.003). Conclusion The newly developed LSO showed no difference regarding its effectiveness and compliance when compared with the existing LSO, but it was more effective in correcting lumbar lordosis.

Purpose: Ruptured abdominal aortic aneurysm (rAAA) is one of the most common aortic emergencies in vascular surgery and is associated with high operative mortality and morbidity rates despite recent treatment advances. We evaluated operative mortality risks for the outcomes of emergency endovascular aneurysm repair (eEVAR) vs. open repair in rAAA. Methods: Twenty patients underwent eEVAR (n = 12) or open repair (n = 8) for rAAA between 2016 and 2020. We adopted the EVAR first strategy since 2018. Primary endpoints included in-hospital mortality and 1-year survival. The outcome variables were analyzed with Fisher exact, Mann-Whitney test, and linear by linear association. The Kaplan-Meier method was used to estimate survival. Results: There were 13 males (65.0%) and the median age of the study cohort was 78.0 years (range, 49–88 years). Inhospital mortality occurred in 7 patients (35.0%); 5 (50.0%) in the early period and 2 (20.0%) in the later period of this series. According to the procedure type, 4 (50.0%) and 3 (25.0%) in-hospital mortalities occurred in the open repair and eEVAR patients, respectively. In 6 patients (50.0%), eEVAR was performed on unfavorable anatomy. The 1-year survival of eEVAR vs. open repair group was 75% ± 12.5% and 50% ± 17.7%, respectively. On univariate analysis, preoperative highrisk indices, postoperative acute renal failure requiring dialysis, pulmonary complications, and prolonged mechanical ventilation were associated with higher operative mortality. Conclusion The current data showed relatively superior outcomes with eEVAR vs. open repair for rAAA, even in some patients with unfavorable anatomy supporting the feasibility, efficacy, and safety of EVAR first strategy.

Purpose: Effectiveness and safety of clofarabine (one of the treatment mainstays in pediatric patients with relapsed/refractory acute lymphoblastic leukemia [ALL]) was assessed in Korean pediatric patients with ALL to facilitate conditional coverage with evidence development. Materials and Methods: In this multicenter, prospective, observational study, patients receiving clofarabine as mono/combination therapy were followed up every 4-6 weeks for 6 months or until hematopoietic stem cell transplantation (HSCT). Response rates, survival outcomes, and adverse events were assessed. Results: Sixty patients (2-26 years old; 65% B-cell ALL, received prior ≥ 2 regimen, 68.3% refractory to previous regimen) were enrolled and treated with at least one dose of clofarabine; of whom 26 (43.3%) completed 6 months of follow-up after the last dose of clofarabine. Fifty-eight patients (96.7%) received clofarabine combination therapy. Overall remission rate (complete remission [CR] or CR without platelet recovery [CRp]) was 45.0% (27/60; 95% confidence interval [CI], 32.4 to 57.6) and the overall response rate (CR, CRp, or partial remission [PR]) was 46.7% (28/60; 95% CI, 34.0 to 59.3), with 11 (18.3%), 16 (26.7%), and one (1.7%) patients achieving CR, CRp, and PR, respectively. The median time to remission was 5.1 weeks (95% CI, 4.7 to 6.1). Median duration of remission was 16.6 weeks (range, 2.0 to 167.6 weeks). Sixteen patients (26.7%) proceeded to HSCT. There were 24 deaths; 14 due to treatment-emergent adverse events. Conclusion Remission with clofarabine was observed in approximately half of the study patients who had overall expected safety profile; however, there was no favorable long-term survival outcome in this study.