The prognostic impact of tumor location in nonmuscle-invasive bladder cancer patients undergoing transurethral resection: insights from a cohort study utilizing Chinese multicenter and SEER registries.

Objective: Most bladder cancers are nonmuscle invasive bladder cancer (NMIBC), and transurethral resection of bladder tumors (TURBT) is the standard treatment. However, postoperative recurrence remains a significant challenge, and the influence of bladder tumor location on prognosis is still unclear. This study aims to investigate how tumor location affects the prognosis of NMIBC patients undergoing TURBT and to identify the optimal surgical approach.

Methods: A multicenter study was conducted, which included Chinese NMIBC data from 15 hospitals (1996-2019) and data from 17 registries of the Surveillance, Epidemiology, and End Results database (SEER) (2000-2020). Patients initially diagnosed with NMIBC and undergoing TURBT or partial cystectomy were analyzed, with cases lost to follow-up or with missing data excluded. The study investigated the overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) among patients with different tumor locations. Kaplan-Meier, Cox regression, and propensity score matching methods were employed to explore the association between tumor location and prognosis. Stratified populations were analyzed to minimize bias.

Results: This study included 118 477 NMIBC patients and highlighted tumor location as a crucial factor impacting post-TURBT prognosis. Both anterior wall and dome tumors independently predicted adverse outcomes in two cohorts. For anterior wall tumors, the Chinese cohort showed hazard ratios (HR) for OS of 4.35 ( P <0.0001); RFS of 2.21 ( P <0.0001); SEER cohort OS HR of 1.10 ( P =0.0001); DSS HR of 1.13 ( P =0.0183). Dome tumors displayed similar trends [Chinese NMIBC cohort OS HR of 7.91 ( P <0.0001); RFS HR of 2.12 ( P <0.0001); SEER OS HR of 1.05 ( P =0.0087); DSS HR of 1.14 ( P =0.0006)]. Partial cystectomy significantly improved the survival of dome tumor patients compared to standard TURBT treatment ( P <0.01).

Conclusion: This study reveals the significant impact of tumor location in NMIBC patients on the outcomes of TURBT treatment, with tumors in the anterior wall and bladder dome showing poor post-TURBT prognosis. Compared to TURBT treatment, partial cystectomy improves the prognosis for bladder dome tumors. This study provides guidance for personalized treatment and prognosis management for NMIBC patients.