Racial disparity in bladder cancer: trends in tumor presentation at diagnosis

Abstract

Purpose: White Americans have a 2-fold higher incidence of bladder cancer than black Americans but the latter have a higher mortality rate. This survival disparity has been attributable largely to the late stage presentation of black patients but other factors likely exist. We examined trends in bladder cancer presentation and survival in white and black patients in a 27-year period to gain additional insight into these factors.

Materials and methods: Using Surveillance, Epidemiology, and End Results Program data trends in tumor presentation, treatment and survival were defined in 93,093 patients, including 89,481 white and 3,612 black patients, with bladder cancer. Parameters were measured during 5 and 7-year intervals from 1973 to 1999. Bivariate relationships between patient/disease characteristics, and the time and survival were explored. Cox proportional hazard models were used to examine the independent effect of parameters on disease specific survival.

Results: Median followup was 10 years. Black patients consistently presented with higher stage and grade tumors (each p <0.001). This was most pronounced in black women. A trend toward earlier stage presentation was observed in black and white patients with time (p = 0.05 and <0.001, respectively). Ten-year survival in black and white patients with similar tumor stage and grade was consistently worse in black patients, except those with metastasis. An adjusted multivariable model demonstrated a persistent survival disadvantage in black patients (HR 1.35, p <0.001).

Conclusions: Racial disparities in bladder cancer stage, grade, treatment and adjusted survival continue to exist between white and black Americans despite improvements in stage presentation and survival of localized and regional disease. These data provide the rationale to study treatment decision making, access, delay and potential bias in the black community.