AUA 2017: Survival Differences Among Patients According to Gender: Critical Evaluation of Radical Cystectomy Use and Delay to Treatment

Boston, MA ( Christopher Kosarek, The University of Texas Medical Branch at Galveston, presented survival differences among bladder cancer patients according to gender assessing radical cystectomy (RC) use and delay to treatment. It is well known men are more commonly diagnosed with bladder cancer, however, women have worse survival outcomes. Prior work by Messer et al. identified the female gender as an adverse prognostic factor, independent of clinical and pathological features for patients undergoing RC. However, the impact of type of treatment, timing to surgery when rendered and survival outcomes according to gender has not been previously examined. Therefore, we provide a population-based assessment in order to discern whether utilization of RC differs according to gender, specifically examining the receipt and timing of RC in relation to survival outcomes.

A total of 49,974 patients aged 66 years or older diagnosed with clinical stage TI-IV N0M0 bladder cancer from January 1, 2001 to December 31, 2011 from SEER-Medicare data were analyzed. Of the 49,974 patients diagnosed with bladder cancer 13,015 (26.0%) were female. While there was no significant difference in bladder cancer diagnosis over the study period, women were older, non−Caucasian race/ethnicity, unmarried, had fewer comorbidities and presented with more advanced disease than men (all p<0.001). Overall 3,321 of the total patients in this study underwent RC, 1,208 (36.4%) of them were female (p<0.001).

Women were significantly more likely to undergo RC across all stages compared to their male counterparts (Stage I: Relative Risk (RR) 1.53, 95% Confidence Interval (CI) = 1.27-1.84, P < 0.001; Stage II: RR 1.52, 95% CI = 1.37-1.70, P < 0.001; Stage III: RR 1.26, 95% CI = 1.15-1.39, P < 0.001; Stage IV: RR 1.37, 95% CI = 1.17-1.47, P < .001). Moreover, there was no significant difference in delay to RC except women with Stage IV disease were less likely to have delay to RC than men (RR 0.77, 95% CI = 0.62-0.95, p=0.017).

Overall survival for all patients (Hazard Ratio [HR] 0.87, 95% CI = 0.85-0.88, p<0.001) and those with stage I disease (HR 0.78, 95% CI 0.75-0.81, p<0.001) was significantly greater for women than men. While there was no difference in overall survival among patients with stage II disease according to gender, women with stage III (HR 1.15, 95% CI 1.02-1.30, p=0.027) and stage IV (HR 1.22, 9% CI 1.12-1.34, p<0.001) bladder cancer had significantly decreased overall survival than their male counterparts. However, women had worse cancer-specific survival when compared to men for all stages (HR 1.15, 95% CI 1.02-1.15, p=0.008) and specifically among those diagnosed with stage II (HR 1.21, CI = 1.10−1.33, P<0.001), stage III (HR 1.48, CI 1.26−1.72, P<0.001), and stage IV (HR 1.33, CI 1.20−1.47, P<0.001) muscle-invasive disease. Using propensity score matching, women had improved overall (HR 0.85, CI 0.82-0.88, P<0.001), but worse cancer-specific survival (HR 1.08, CI 1.02-1.15, P=0.008) than men, respectively.

In conclusion, gender differences in survival persist despite women significantly more likely to undergo treatment including RC. These findings were independent of clinical stage. Delay from diagnosis to surgery did not account for the decreased cancer-specific survival among women, suggesting inherent characteristics of tumor biology likely impact gender differences in survival. These findings support further research to discern the biological underpinnings of bladder carcinogenesis according to gender.

Presented By: Christopher Kosarek, The University of Texas Medical Branch at Galveston

Written By: Stephen B. Williams, M.D., Assistant Professor in Urology, The University of Texas Medical Branch, Galveston, TX. and Ashish M. Kamat, M.D. Professor, Department of Urology, Division of Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX.

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA