Impact of age at diagnosis on racial disparities in endometrial cancer patients.

INTRODUCTION: Although black patients with endometrial cancer (EC) have worse survival compared with white patients, the interaction between age/race has not been examined. The primary objective was to evaluate the impact of age at diagnosis on racial disparities in disease presentation and outcome in EC.

METHODS: We evaluated women diagnosed with EC between 1991 and 2010 from the Surveillance, Epidemiology, and End Results. Mutation status for TP53 or PTEN, or with the aggressive integrative, transcript-based, or somatic copy number alteration-based molecular subtype were acquired from the Cancer Genome Atlas. Logistic regression model was used to estimate the interaction between age and race on histology. Cox regression model was used to estimate the interaction between age and race on survival.

RESULTS: 78,184 white and 8518 black patients with EC were analyzed. Median age at diagnosis was 3-years younger for black vs. white patients with serous cancer and carcinosarcoma (P<0.0001). The increased presentation of non-endometrioid histology with age was larger in black vs. white patients (P<0.0001). The racial disparity in survival and cancer-related mortality was more prevalent in black vs. white patients, and in younger vs. older patients (P<0.0001). Mutations in TP53, PTEN and the three aggressive molecular subtypes each varied by race, age and histology.

CONCLUSIONS: Aggressive histology and molecular features were more common in black patients and older age, with greater impact of age on poor tumor characteristics in black vs. white patients. Racial disparities in outcome were larger in younger patients. Intervention at early ages may mitigate racial disparities in EC.