Background:To test the effect of radical cystectomy (RC) with chemotherapy vs only chemotherapy on overall mortality (OM) in metastatic urothelial carcinoma of the urinary bladder (mUCUB).Methods: Within the Surveillance, Epidemiology, and End Results registry (2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016), we identified patients with mUCUB. Stratification was made according to treatment: RC with chemotherapy vs only chemotherapy. Kaplan-Meier plots and multivariable Cox regression models were used before and after 1:1 propensity score (PS) matching and inverse probability of treatment weighting (IPTW).Results: Of 2414 patients with mUCUB, 500 (21.0%) vs 1914 (79.0%) were treated with RC with chemotherapy vs only chemotherapy, respectively. In multivariable Cox regression models, RC with chemotherapy was associated with lower OM in the overall cohort (hazard ratio [HR], 0.5; P < .001), after 1:1 PS matching (HR, 0.5; P < .001), after IPTW (HR, 0.5; P < .001) and after accounting for number and location of metastases (HR, 0.5; P < .001). However, higher overall survival after RC with chemotherapy was only observed in patients with one metastatic site (21 vs 16 months; P = .001).
Conclusion:In contemporary patients with mUCUB, RC with chemotherapy is associated with lower OM rates, relative to chemotherapy alone, but only in patients with a single metastatic site. These individuals accounted for the vast majority of patients in whom an RC was performed, despite the presence of metastatic disease. K E Y W O R D S chemotherapy, metastatic urothelial carcinoma of the urinary bladder, radical cystectomy