Oncological outcomes of concurrent nephroureterectomy during radical cystectomy: A propensity score-matched analysis with multivariable adjustment from Korean multicenter database

Abstract

Background: Oncological safety and prognostic implications of concurrent nephroureterectomy (RNU) performed during radical cystectomy (RCx) for bladder cancer remain controversial due to potential selection bias in previous studies. Objectives: To evaluate oncological outcomes of concurrent RNU during RCx using propensity score matching (PSM) and multivariable Cox regression to minimize selection bias and identify independent prognostic factors. Materials and methods: We analyzed 2944 patients who underwent RCx from a Korean multicenter database (2000-2022). Patients were stratified into RCx only (n = 2627) and concurrent RCx + RNU (n = 317) groups. PSM was performed using age, sex, BMI, ASA score, and clinical TNM stage, creating 284 matched pairs. Multivariable Cox proportional hazards regression was performed adjusting for demographic, clinical, and pathologic variables. Primary outcomes were recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS). Results: After PSM, recurrence remained significantly higher in RCx + RNU (60.4% vs 40.9%, p < 0.001), with 5-year RFS of 32.8% vs 51.6% (p = 0.0005). However, CSS (68.4% vs 71.6%, p = 0.408) and OS (52.9% vs 55.4%, p = 0.830) at 5 years showed no significant differences. Multivariable Cox regression confirmed that concurrent RNU was not an independent prognostic factor (RFS: HR 1.38, p = 0.106; CSS: HR 1.27, p = 0.223; OS: HR 1.11, p = 0.443). Independent adverse prognostic factors included pathologic N+ disease (CSS: HR 2.69, p < 0.001; OS: HR 1.88, p < 0.001), lymphovascular invasion (RFS: HR 1.81, p = 0.014; CSS: HR 1.92, p = 0.002; OS: HR 1.67, p = 0.002), and ASA score >= 3 (RFS: HR 1.85, p = 0.002). Conclusion: Concurrent RNU during RCx is associated with higher recurrence rates but does not compromise cancer-specific or overall survival and is not an independent prognostic factor after adjusting for pathologic characteristics. The higher recurrence reflects more aggressive underlying disease biology rather than adverse surgical effects. One-stage concurrent RNU is oncologically safe in appropriately selected patients but necessitates intensive surveillance.