Missed opportunity: An intersectional approach to disparities in long-term survival in bladder cancer.

Abstract

476 Background: For individuals with muscle-invasive bladder cancer (MIBC), studies focused on racial disparities have shown black race is associated with 21% lower odds of guideline-based treatment (GBT) and differences in treatment explain 35% of observed black-white differences in survival. To characterize how the interaction between race/ethnicity and receipt of GBT drive within- and between-race differences in survival for black, white, and Latino individuals with MIBC. Methods: We identified a cohort of individuals with cT2-4 MIBC from 2004-2013 in the National Cancer Database. GBT was defined by American Urological Association guidelines. A Cox proportional hazards model of patient mortality estimated effects of patient GBT status, race/ethnicity, and the GBT-by-race/ethnicity interaction, adjusting for covariates. Results: Of 54,910 MIBC individuals with 125,821 person-years of post-treatment observation (max=11 years), 90.1% were white, 6.9% black, and 3.0% Latino. Half (50.2%) received GBT. Averaging across GBT status, Latino individuals had lower hazard of death compared to black (HR 0.81, 95% CI 0.75-0.87) and white individuals (HR 0.92, 0.86-0.98). With GBT, Latino and white individuals had similar outcomes (HR=1.00, 0.91-1.10) and both groups fared significantly better than black individuals (HR=0.88, 0.79-0.99 and HR=0.88, 0.83-0.94, respectively). Without GBT, Latino individuals fared better than white (HR=0.85, 0.77-0.93) and black individuals (HR=0.74, 0.67-0.82) while white individuals fared better than black individuals (HR=0.87, 0.83-0.92). Latino without GBT fared better than black individuals with GBT (H=0.98, 0.88-1.09), although not statistically significant. Conclusions: Our study finds that not only are GBT levels generally low, which is concerning, but there is also an apparent 'under-allocation' of GBT to a patient group who arguably needs it the most-- black individuals. Future efforts to improve the delivery of GBT, a factor directly impacted by urologic care providers, may mitigate the race-based survival differences observed in individuals with MIBC.