Racial and ethnic differences in type II endometrial cancer mortality outcomes: The contribution of sociodemographic, clinicopathologic, and treatment factors

Objective: The burden of type II endometrial cancer (EC) is rising dramatically in the U.S. Although type II EC disproportionately affects Black women, the magnitude of racial/ethnic differences in type II EC mortality outcomes and factors underlying these differences remain understudied. We examined racial/ethnic differences in cancer-specific and overall mortality in women with type II EC and quantified the extent to which mortality differences are mediated by sociodemographic, clinicopathologic, and treatment factors.

Methods: 14,710 women ≥18 years with type II EC from 2007 to 2016 were identified from the Surveillance, Epidemiology, and End Results database. The association between race/ethnicity (non-Hispanic White [NHW], non-Hispanic Black [NHB], Hispanic, and non-Hispanic Asian/Pacific Islander [NHAPI]) and cancer-specific and overall mortality was examined. Mediation analysis was used to identify factors underlying differences in mortality outcomes.

Results: NHB women had a higher risk of cancer-specific mortality than NHW women (hazard ratio [HR]: 1.22, 95% CI: 1.12-1.33), whereas NHAPI (HR: 0.88, 95% CI: 0.78-0.99) and Hispanic women (HR: 0.91, 95% CI: 0.81-1.01) had a lower risk of cancer-specific mortality than NHW women. Differences in clinicopathologic (stage, grade, histologic subtype), sociodemographic (insurance type, geographic region and location, neighborhood socioeconomic status), and treatment factors (treatment type, lymphadenectomy) explained 43.5%, 8.1%, and 7.3% of the difference in cancer-specific mortality between NHB and NHW women, respectively. Similar results were noted for overall mortality.

Conclusions: Multidisciplinary and multilevel approaches that integrate and address social and biological factors are needed to reduce the disproportionate burden of type II EC mortality in NHB women.