Purpose: This study evaluated the feasibility of radical nephrectomy and thrombectomy without cardiopulmonary bypass (CPB) in patients with renal cell carcinoma (RCC) and level IV venous tumor thrombus, compared with CPB-assisted surgery. Materials and Methods: This retrospective cohort study analyzed patients with RCC and level IV venous tumor thrombus who underwent surgery at a single center between 2014 and 2020. Feasibility of non-CPB surgery was assessed by comparing perioperative safety-related outcomes, overall survival (OS), and progression-free survival (PFS) between the non-CPB and CPB groups. Perioperative outcomes included operative time, blood loss, severe complications (Clavien-Dindo classification grade ≥III), intensive care unit (ICU) stay, and mortality. Kaplan-Meier analysis and generalized Wilcoxon tests were used to compare survival outcomes. Results: A total of 16 patients met eligibility criteria: 5 underwent surgery without CPB, and 11 underwent CPB-assisted surgery. Median operative time was similar between the CPB and non-CPB groups (490 minutes vs. 480 minutes, p=0.650). Compared with the CPB group, blood loss was lower in the non-CPB group (4000 mL vs. 1080 mL, p=0.333). Severe complications occurred in 36.4% of CPB patients and 0% of non-CPB patients (p=0.245). ICU stay was comparable between the non-CPB and CPB groups (2 days vs. 3 days, p=0.356). OS did not differ significantly between groups (p=0.180), whereas PFS was longer in the non-CPB group (p=0.041). Conclusions Radical nephrectomy and thrombectomy without CPB appears feasible and may be associated with lower perioperative morbidity and blood loss without compromising oncologic outcomes. Non-CPB surgery should be considered in selected patients with level IV venous tumor thrombus when technically feasible.

Purpose: To develop and validate an artificial intelligence (AI)-based personalized outcome prediction model for upper-urinary tract urothelial carcinoma patients undergoing radical nephroureterectomy. Materials and Methods: Data from patients who underwent radical nephroureterectomy between 2010 and 2020 across three hospitals were retrospectively analyzed. A model was developed using one tertiary center’s data and externally validated with data from two other hospitals. An AI model using XGBoost as risk estimator and bootstrapped Weibull Accelerated Failure Time model for 10-year survival probability was employed. Hyperparameter tuning used Optuna method. Model efficacy was assessed using concordance index, average Brier score, D-calibration, and six-month interval time-dependent area under the curve (AUC). Results: Of 1,039 patients, 627 qualified after excluding 50 with neoadjuvant chemotherapy. Model development used 564 patients (507 training, 57 test) with 9:1 stratified random split, plus 63 for internal validation and 362 for external validation. Significant parameters included preoperative glomerular filtration rate (p<0.001), hydroureteronephrosis (p=0.013), pathological N stage (p<0.001), concurrent carcinoma in situ (p<0.001), disease progression (p<0.001), and survival rate (p<0.001). Disease-free survival (DFS) model’s concordance index: internal validation 0.789, external validations 0.734 and 0.771. Overall survival (OS) model’s concordance index: internal validation 0.819, external validations 0.780 and 0.771. Mean time-dependent AUC was 0.66–0.77 for DFS and 0.67–0.80 for OS during 10-year periods. Conclusions AI-based model effectively predicts disease-free and OS outcomes for upper-urinary tract urothelial carcinoma patients with post-radical nephroureterectomy, showcasing robust performance across multicenter settings.

Purpose: Determining the optimal surgical approach for patients with T1 renal tumors requires balancing long-term oncological and renal functional outcomes. Using machine learning algorithms, we aimed to develop a model to predict both outcomes simultaneously, according to each radical (RN) and partial nephrectomy (PN). Materials and Methods: Using demographic and preoperative variables of 823 patients with clinical T1N0M0 renal tumors who underwent PN or RN between 2007 and 2019, we employed 5 different machine learning algorithms—general linear model (GLM), extreme gradient boosting (XgBoost), gradient boosting machine, distributed random forest, deep learning—and compared to predict recurrence probability and estimated glomerular filtration rate (eGFR) at 5-year after surgery. Model performance for recurrence prediction was evaluated with area under the curve receiver operating characteristic, area under the precision-recall curve, and log-loss, while eGFR prediction was assessed using root mean square error (RMSE) and R2. Results: Of the 823 patients, 463 (56.3%) had T1a tumors and 487 (59.2%) underwent PN. The median preoperative eGFR was 99.1 mL/min/1.73 m2, and at 5 years postoperative it was 70.4 after RN and 92.0 after PN. Recurrence within 5 years was observed in 1.1% and 4.2% of T1a and T1b cohorts, respectively. We developed models based on clinically significant preoperative variables. Across the models, the XGBoost demonstrated the highest accuracy for predicting 5-year recurrence, with superior recall (0.0252) and precision (0.0465) compared to other algorithms. For 5-year eGFR prediction, the GLM outperformed other models, achieving RMSE of 12.700 and R2/sup> of 0.694 on the test set. The 2 models were integrated into a single online interface. Conclusion We developed a tool to reliably predict 5-year oncological and renal functional outcomes following each nephrectomy type in patients with T1 renal tumors. Further multi-institutional validation is needed to confirm its generalizability and applicability across diverse clinical settings.

Background: In patients with metastatic renal cell carcinoma (mRCC), sites of metastatic involvement have been reported to be associated with a difference in survival. However, the frequency and survival according to different sites of metastases in Korean patients with mRCC remain unclear. Therefore, this study aimed to assess the frequency of metastatic site involvement and the association between sites of metastatic involvement and survival in Korean patients with mRCC. Methods: This retrospective study used the multicenter cohort of the Korean Renal Cancer Study Group mRCC database to identify patients who started targeted therapy between December 2005 and March 2018. Data on the frequency of metastatic organ involvement at the time of mRCC diagnosis and oncologic outcomes according to different sites of metastasis were analyzed. Results: A total of 1,761 patients were eligible for analysis. Of the 1,761 patients, 1,564 (88.8%) had clear cell RCC, and 1,040 (59.1%) had synchronous metastasis. The median number of metastasis sites was 2 (interquartile range [IQR], 1–6). The median age at the initiation of systemic therapy was 60 years (IQR, 29–88), 1,380 (78.4%) were men, and 1,341 (76.1%) underwent nephrectomy. Based on the International Metastatic Renal Cell Carcinoma Database Consortium model, patients were stratified into favorable-, intermediate-, and poor-risk groups with 359 (20.4%), 1,092 (62.0%), and 310 (17.6%) patients, respectively. The lung (70.9%), lymph nodes (37.9%), bone (30.7%), liver (12.7%), adrenal gland (9.8%), and brain (8.2%) were the most common sites of metastasis, followed by the pancreas, pleura, peritoneum, spleen, thyroid, and bowel. Among the most common sites of metastasis (> 5%), the median cancer-specific survival (CSS) ranged from 13.9 (liver) to 29.1 months (lung). An association was observed between liver, bone, and pleural metastases and the shortest median CSS (< 19 months). Conclusion In Korean patients with mRCC, metastases to the lung, lymph nodes, bone, liver, adrenal gland, and brain were more frequent than those to other organs. Metastases to the liver, bone, and pleura were associated with poor CSS. The findings of this study may be valuable for patient counseling and guiding future study designs.

Purpose: This study investigated the effect of administering tamsulosin before surgery on the successful insertion of a 12/14 French (F) ureteral access sheath (UAS) during the procedure, as well as the impact of preoperative and postoperative tamsulosin use on symptoms related to the ureteral stent. Materials and Methods: This study was a randomized, single-center, double-blinded, placebo-controlled trial involving 200 patients who underwent unilateral retrograde intrarenal surgery. Patients received either tamsulosin (0.4 mg) or placebo 1 week before surgery until stent removal. Patients were randomly assigned to one of four groups. Group 1 received tamsulosin throughout the study period. Group 2 received tamsulosin before surgery and placebo after surgery. Group 3 received placebo before surgery and tamsulosin after surgery. Group 4 received placebo before and after surgery. The USSQ (Ureteral Stent Symptom Questionnaire) was completed between postoperative days 7 and 14 immediately before stent removal. Results: A total of 160 patients were included in this analysis. Their mean age was 55.0±11.0 years, and 48 patients (30.0%) were female. In the group that received preoperative tamsulosin, the success rate of 12/14F UAS deployment was significantly higher than that of the preoperative placebo group (88.0 vs. 75.3%, p=0.038). Preoperative and postoperative tamsulosin did not significantly alleviate symptoms related to the ureteral stent. Conclusions Our results revealed that preoperative administration of tamsulosin improved the success of larger-sized UAS, whereas preoperative and postoperative tamsulosin use did not significantly alleviate symptoms related to ureteral stents.

Purpose: We evaluated the risk factors associated with failure to complete gemcitabine–cisplatin (GP) neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer (MIBC). Materials and Methods: In total, 231 patients with MIBC treated with NAC before undergoing radical cystectomy between 2013 and 2022 participated in this study. Logistic regression analysis was performed to assess the relationship between the likelihood of incomplete NAC and clinical and demographic variables, including age, sex, hypertension (HTN), diabetes mellitus (DM), prechemotherapy glomerular filtration rate, clinical T stage, clinical N stage, and body mass index (BMI). Results: Of 231 patients, 209 (90.5%) and 22 (9.5%) completed and discontinued the NAC course, respectively. The mean age was 66.13±9.15, 65.63±9.07, and 70.86±8.66 years for the total sample, continuation, and discontinuation groups, respectively (p=0.010). No significant inter-group differences in sex, HTN, height, weight, BMI, pre-chemotherapy glomerular filtration rate, clinical T stage, or clinical N stage were observed. According to the results of the multivariable analysis, age (odds ratio [OR] 1.076, 95% confidence interval [CI] 1.013–1.143, p=0.018) and the presence of DM (OR 2.541, 95% CI 1.028–6.281, p=0.043) were significantly associated with NAC discontinuation. Conclusions Thus, older age and presence of DM are potential risk factors for GP NAC discontinuation in patients with MIBC.Further studies are required to validate our findings and develop strategies to minimize the rate of GP NAC discontinuation in this population.