Purpose: This study aims to develop and implement an economic evaluation using a micro-costing approach to provide a precise and transparent analysis of the direct costs of cystoscopic procedures in Korean hospitals. The study seeks to identify key cost components and evaluate whether current reimbursement rates accurately reflect these direct costs. Materials and Methods: Significant variations in cost items were identified across different studies. An economic evaluation was conducted using a micro-costing methodology for the cost analysis of cystoscopic procedures, developed through literature review, data collection from studies, and expert consultations. Results: Gangnam Severance Hospital (GSH) performed 2,188 cystoscopic procedures, including 1,847 cystoscopies and 341 JJ stent removals, with average costs of $100.8 and $110.6, respectively. At National Health Insurance Service Ilsan Hospital (NHIMC), 1,463 procedures were performed, including 1,167 cystoscopies and 296 JJ stent removals, with average costs of $119.2 and $125.3. Cystoscopy costs at GSH were driven by reprocessing ($45.8, 45.4%) and equipment ($33.1, 32.9%), while NHIMC’s were $52.5 (44.0%) for equipment and $48.7 (40.8%) for reprocessing. Both hospitals incurred financial losses, with NHIS (National Health Insurance Service) covering only about 71.7% and 60.6% of costs for cystoscopy, and 71.0% and 62.7% for JJ stent removal. Conclusions The significant discrepancy between HIRA (Health Insurance Review & Assessment Service)’s estimated costs and those identified here suggests that current fees for cystoscopic procedures may be underestimated and require reassessment.Given the results, reevaluating these rates is essential to ensure fair compensation for healthcare providers and to deliver optimal patient care.

Purpose: The incidence and prognostic implications of atrial fibrillation (AF) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI) are controversial, especially for Korean patients. Furthermore, the pattern of antithrombotic therapy for these patients is unknown. The present study sought to identify the impact of AF on Korean patients undergoing TAVI and demonstrate the status of antithrombotic therapy for these patients. Materials and Methods: A total of 660 patients who underwent TAVI for severe AS were recruited from the nationwide K-TAVI registry in Korea. The enrolled patients were stratified into sinus rhythm (SR) and AF groups. The primary endpoint was all-cause death at 1-year. Results: AF was recorded in 135 patients [pre-existing AF 108 (16.4%) and new-onset AF 27 (4.1%)]. The rate of all-cause death at 1 year was significantly higher in patients with AF than in those with SR [16.2% vs. 6.4%, adjusted hazard ratio (HR): 2.207, 95% confidence interval (CI): 1.182–4.120, p=0.013], regardless of the onset timing of AF. The rate of new pacemaker insertion at 1 year was also significantly higher in patients with AF than in those with SR (14.0% vs. 5.5%, adjusted HR: 3.137, 95%CI: 1.621–6.071, p=0.001).Among AF patients, substantial number of patients received the combination of multiple antithrombotic agents (77.8%), and the most common combination was that of aspirin and clopidogrel (38.1%). Conclusion AF was an independent predictor of 1-year mortality and new pacemaker insertion in Korean patients undergoing TAVI.

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/Aims: Cholangiocarcinoma frequently recurs even after curative resection. Expression levels of proteins such as epidermal growth factor receptor (EGFR), Snail, epithelial cadherin (E-cadherin), and interleukin-6 (IL-6) examined by immunohistochemistry have been studied as potential prognostic factors for cholangiocarcinoma. The aim of this study was to investigate significant factors affecting the prognosis of resectable cholangiocarcinoma. Methods: Ninety-one patients who underwent surgical resection at Samsung Medical Center for cholangiocarcinoma from 1995 to 2013 were included in this study. Expression levels of Ecadherin, Snail, IL-6, membranous EGFR, and cytoplasmic EGFR were analyzed by immunohistochemistry using tissue microarray blocks made from surgical specimens. Results: Patients with high levels of membranous EGFR in tissue microarrays had significantly shorter overall survival (OS) and disease-free survival (DFS): high membranous EGFR (score 0–2) 38.0 months versus low membranous EGFR (score 3) 14.4 months (p=0.008) and high membranous EGFR (score 0–2) 23.2 months versus low membranous EGFR (score 3) 6.1 months (p=0.004), respectively. On the other hand, E-cadherin, Snail, cytoplasmic EGFR, and IL-6 did not show significant association with OS or DFS. Patients with distant metastasis had significantly higher IL-6 levels than those with locoregional recurrence (p=0.01). Conclusions This study showed that overexpression of membranous EGFR was significantly associated with shorter OS and DFS in surgically resected bile duct cancer patients. In addition, higher IL-6 expression was a predictive marker for recurrence in cholangiocarcinoma patients with distant organ metastasis after surgical resection.

Background/Aims: As pancreatic mucinous cystic neoplasms (MCNs) are considered premalignant lesions, the current guidelines recommend their surgical resection. We aimed to investigate the concordance between preoperative and postoperative diagnoses and evaluate preoperative clinical parameters that could predict the malignant potential of MCNs. Methods: Patients who underwent surgical resection at Samsung Medical Center for pancreatic cystic lesions and whose pathology was confirmed to be MCN, between July 2000 and December 2017, were retrospectively analyzed. Results: Among a total of 132 patients 99 (75%) were diagnosed with MCN preoperatively. The most discordant preoperative diagnosis was an indeterminate pancreatic cyst. The proportion of male patients was higher (24.2% vs 7.1%, p=0.05) in the diagnosis-discordance group and the presence of worrisome features in radiologic imaging studies, such as wall thickening/enhancement (12.1% vs 37.4%, p=0.02) or solid component/mural nodule (3.0% vs 27.3%, p=0.02), was lower in the diagnosis-discordance group. The presence of symptoms (57.7% vs 34.9%, p=0.02), tumor size greater than 4 cm (80.8% vs 55.7%, p=0.04), and radiologic presence of a solid component/mural nodule (42.3% vs 16.0%, p=0.01) or duct dilatation (19.2% vs 6.6%, p=0.01) were significantly associated with malignant MCNs. Conclusions In our study, the overall diagnostic concordance rate was confirmed to be 75%, and our findings suggest that MCNs have a low malignancy potential when they are less than 4cm in size, are asymptomatic and lack worrisome features on preoperative images.

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.

Purpose: An adequate minimal surgical margin for partial nephrectomy (PN) has not yet been conclusively established. Therefore, we aimed to compare PN recurrence rates according to surgical margin status and to establish an adequate minimal surgical margin. Materials and Methods: We retrospectively studied patients with clinically localized renal cell carcinoma who underwent PN between 2005 and 2014. Surgical margin width (SMW) was assessed for all surgical tissues and divided into three groups: SMW <1 mm, SMW ≥1 mm, and positive surgical margin (PSM). The data were analyzed using the Kaplan-Meier method with log-rank tests and multivariate Cox regression models. Results: Of 748 patients (median age, 55 years; interquartile range, 46–64 years; 220 female), 704 (94.2%) and 44 (5.8%) patients had negative and PSMs, respectively. Recurrence-free survival was significantly lower in patients with PSMs (p<0.001) and was not significantly different between SMW ≥1 mm and <1 mm groups (p=0.604). PSM was a significant predictor of recurrence (hazard ratio: 8.03, 95% confidence interval: 2.74–23.56, p<0.001), in contrast to SMW <1 mm (p=0.680). Conclusion A PSM after PN significantly increases the risk of recurrence. We discovered that even a submillimeter safety surgical margin may be enough to prevent recurrence. To maximize normal renal parenchyma preservation and to avoid cancer recurrence in renal parenchymal tumor patients, PN may be a safe treatment, except for those with a PSM in the final pathology.

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.