Black/white differences in bladder cancer patient survival.

Black bladder cancer patients have been found to have a substantially poorer survival experience than white patients; the 5-year relative survival rates are 71% for whites and 54% for blacks. To explore this difference in survival, data were analyzed on 4289 white and 380 black bladder cancer patients diagnosed during the period 1977-80 in three geographic areas covered by the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. The orientation of the analysis was to identify variables, using multivariable procedures, that were not only prognostic but which also were important in regard to explaining black/white differences in patient survival. Such variables are referred to as explanatory variables. Three variables were analyzed in regard to their importance as explanatory variables, i.e. histologic type, stage, and histologic grade, and all were found to be of roughly equal importance. The effects of other factors on black/white differences in survival are also discussed including the possible importance of lead-time bias and the possible lack of diagnosis of the more benign forms of bladder cancer in blacks.