We investigated comorbidities and endometrial cancer survival by ethnicity because Hispanic whites (HWs) have worse survival than non-Hispanic whites (NHWs).

An endometrial cancer cohort (1992–2004) established with the Surveillance, Epidemiology and End Results-Medicare-linked database (n = 3,286) was followed through 2007. Endometrial cancer-specific and other cause mortality were evaluated with multivariate hazard ratios (mHRs).

HWs were more likely than NHWs to have regional/distant disease (31.7 vs. 24.8 %), diabetes (31.7 vs. 11.0 %), and hypertension (49.4 vs. 37.6 %). HWs had poorer endometrial cancer-specific survival than NHWs (age-adjusted HR = 1.28; 95% CI 1.01–1.61), but not after adjustment for tumor characteristics and treatment (mHR = 1.02; 95% CI 0.81–1.29). In contrast, even after adjustment for cancer-related factors, other cause mortality in HWs was elevated (mHR = 1.27; 95% CI 1.01–1.59), but not after further adjustment for comorbid conditions (mHR = 1.07; 95% CI 0.85–1.35).

Comorbidities, particularly diabetes, were more common in HWs than in NHWs and impacted other cause mortality. Improving diabetes management may be an effective means of improving other cause mortality. This may be particularly true for HWs, given their particularly high prevalence of diabetes.