Analysis of racial differences in incidence, survival, and mortality for malignant tumors of the uterine corpus

Abstract

BACKGROUND: In the United States, incidence rates for malignant tumors of the uterine corpus are lower among blacks than among whites, whereas mortality rates are higher among blacks. Reasons for the higher level of mortality among blacks have been debated. METHODS: Using data from the Surveillance, Epidemiology, and End Results program, the authors compared incidence rates by histopathologic type for malignant tumors of the uterine corpus (including uterus, not otherwise specified) during the period 1992-1998 among white Hispanic, black, and white non-Hispanic patients. The authors also compared cumulative relative survival rates for blacks and whites by histopathologic type and by other factors, and they calculated estimated type-specific mortality rates. RESULTS: Overall incidence (per 100,000 woman-years) of corpus malignancy was significantly lower among white Hispanics (14.04; 95% confidence interval [CI], 13.39-14.72) and blacks (15.31; 95% CI, 14.61-16.04) compared with white non-Hispanics (23.43; 95% CI, 23.06-23.81). Compared with white non-Hispanics, blacks had significantly higher incidence rates of serous/clear cell carcinoma (rate ratio, 1.85; 95% CI, 1.61-2.12), carcinosarcoma (rate ratio, 2.33; 95% CI, 1.99-2.72), and sarcoma (rate ratio, 1.56; 95% CI, 1.31-1.86). Survival was worse for blacks than for whites in every histopathologic category and in 'usual' types of endometrial adenocarcinoma, stratified by stage, grade, and age. Rare aggressive tumor types accounted for 53% of mortality among blacks, compared with 36% among whites. CONCLUSIONS: Less favorable outcomes for usual types of endometrial adenocarcinoma and for rare aggressive tumors contribute equally to the relatively high mortality due to corpus cancer among black women.