Survival differences among patients with bladder cancer according to sex: Critical evaluation of radical cystectomy use and delay to treatment

Objective Sex differences in bladder cancer survival are well known. However, the effect of type of treatment, timing to surgery when rendered, and survival outcomes according to sex have not been extensively examined. Given the relatively low incidence of bladder cancer in females, large multicenter and population-based studies are required to elucidate sex differences in survival. In this study, we sought to characterize the effect of use and timing of radical cystectomy (RC) according to sex and survival outcomes. Methods A total of 9,907 patients aged 66 years or older diagnosed with clinical stage II to IV N0M0 bladder cancer from January 1, 2001 to December 31, 2011 from Surveillance, Epidemiology, and End Results-Medicare data were analyzed. We used multivariable regression analyses to identify factors predicting the use and delay of RC. Cox proportional hazards models were used to analyze survival outcomes. Results Of the 9,907 patients diagnosed with bladder cancer, 3,256 (32.9%) were females. Women were significantly more likely to undergo RC across all stages compared to their male counterparts (stage II: relative risk [RR] = 1.48, 95% CI: 1.33–1.65, P<0.001; stage III: RR = 1.24, 95% CI: 1.13–1.37, P<0.001; and stage IV: RR = 1.33, 95% CI: 1.19–1.49, P<0.001). Moreover, there was no significant difference in delay to RC according to sex across all clinical stages. Using propensity score matching, women had worse overall (hazard ratio = 1.07; CI: 1.01–1.14; P = 0.024), and worse cancer-specific survival (hazard ratio = 1.26; CI: 1.17–1.36, P<0.001) than men. Conclusion Sex differences persist with women who are significantly more likely to undergo RC independent of clinical stage. However, women have significantly worse survival than men. Delay from diagnosis to surgery did not account for this decreased survival among women.