Survival outcomes and temporal trends of non-surgical management versus radical cystectomy in non-organ-confined urothelial bladder cancer.

Objective: To investigate whether bimodal therapy (BMT) or trimodal therapy (TMT) differ from radical cystectomy (RC) + perioperative chemotherapy (CT) in cancer control outcomes among patients with non-organ-confined (NOC; T3-4 and/or N1-3) urothelial carcinoma of the urinary bladder (UCUB).

Methods: Within the SEER database (2005-2021) rates of BMT vs. TMT vs. RC+CT use in NOC UCUB patients were tabulated. Nearest-neighbor 1:1 propensity score matching (PSM) for age, sex, stage and race/ethnicity was applied. Cumulative incidence plots depicted five-year cancer-specific (CSM) and other-cause mortality (OCM) rates. Univariable and multivariable competing risks regression (CRR) models were fitted. Sensitivity analyses focused within T3-4,N0 patients.

Results: Of 7,401 NOC UCUB patients, 1,645 (22.2%) received BMT vs. 884 (11.9%) TMT vs. 4,872 (65.8%) RC+CT. Over the study period, BMT and TMT rates have not significantly changed. After PSM, five-year CSM rate was 66.2% after BMT vs. 44.9% after RC+CT and BMT was associated with 2.1-fold higher CSM relative to RC+CT (multivariable HR [mHR]: 2.12, p<0.001). After PSM, five-year CSM rates was 61.1% after TMT vs. 46.6% after RC and TMT was associated with 1.6-fold higher CSM relative to RC (mHR: 1.63, p<0.001). Virtually the same findings were found within T3-4,N0 patients.

Conclusions: Approximately three out of ten NOC UCUB patients were treated with either BMT or TMT. However, such practice was invariably associated with higher CSM relative to RC+CT. These observations should be discussed at clinical decision making and prior to informed consent.