Introduction: There are well demonstrated gender- and sex-based influences on bladder cancer incidence, stage at presentation and, potentially, therapeutic outcomes. Less clear is whether, stage for stage, there are differential outcomes between women and men with muscle invasive bladder cancer (MIBC) treated for cure. The purpose of this study is to examine whether there are gender-related differences in survival outcomes for those patients treated with trimodal therapy (TMT) for MIBC. Methods: This retrospective, multi-center study reports on 542 patients that underwent curative intent radiotherapy with concurrent chemotherapy, for MIBC across academic centers in Canada. Survival outcomes, including overall survival (OS) and cancer specific survival (CSS), were estimated using the Kaplan-Meier method. Multivariable regression models were performed to explore independent predictors of survival outcomes. Results: There were 397 men and 145 women who underwent trimodal therapy for MIBC across the participating centers with a total median follow-up 30 months [95% CI 27-32]. There were no clinically significant gender-related differences in baseline cancer characteristics or treatment specifics identified. Median OS for men was 81 months, [95% CI 71 – 95] versus women 52 months, [95% CI 52 – 154]. Median CSS for men was not reached, [95% CI not reached] versus women 129 months, [95% CI 72-not reached]. Median disease free survival for men was 28 months, [95% CI 22 – 44] versus women 29 months, [95% CI 18 – 52]. In multivariable analysis, gender 1.41 [95% CI 1.02-1.95, p=0.035] was associated with OS favouring men, although no differences were observed for CSS. ECOG performance status, tumour stage, presence of hydronephrosis, and RT volume were all independently associated with both CSS and OS in multivariable analysis. Conclusions: Similar to previous findings suggesting gender-related differences in the management and outcomes of patients with MIBC treated with cystectomy, this large cohort multi-center study did demonstrate some differences in survival outcomes between men and women amongst those receiving TMT. SOURCE OF Funding: None
