The Growing Burden of Endometrial Cancer: A Major Racial Disparity Affecting Black Women

BACKGROUND: In contrast with the decreasing incidence seen for most cancers, endometrial cancer has been increasing in the United States. We examined whether the increasing incidence and mortality from endometrial cancer are equally distributed by race/ethnicity and tumor histologic subtype. METHODS: Surveillance, Epidemiology, and End Results (SEER) endometrial cancer incidence and mortality data were obtained from 2000 to 2011. Age-adjusted incidence and incidence-based mortality rates, 95% confidence intervals, and annual percent changes (APC) were calculated. Rate ratios were calculated to compare racial/ethnic groups. Five-year relative survival rates were presented to explore survival by stage at diagnosis. RESULTS: Incidence rates for endometrial cancers are rising across all racial/ethnic groups, with the greatest APC seen among non-Hispanic black (NHB) and Asian women (APC, 2.5 for both). NHB women have significantly higher incidence rates of aggressive endometrial cancers (clear cell, serous, high-grade endometrioid, and malignant mixed Mullerian tumors) compared with non-Hispanic white (NHW) women. Hispanic and Asian women have incidence rates equal to or lower than NHW women for all tumor subtypes. For nearly every stage and subtype, the 5-year relative survival for NHB women is significantly less than NHW women, whereas Hispanic and Asian women have the same or better survival. CONCLUSIONS: Endometrial cancer incidence is increasing for all women, particularly the aggressive subtypes. The disparity associated with excess incidence for these aggressive histologic subtypes and poorer survival is limited to NHB women. IMPACT: Increasing rates of aggressive endometrial cancers may widen the survival disparity between NHW and NHB women.