Recent racial/ethnic disparities in cancer-specific mortality among patients diagnosed with rectal cancer

African American patients frequently receive nonstandard treatment and demonstrate poorer overall survival (OS) outcomes compared to White patients. Our objective was to analysis whether racial/ethnic disparities in rectal cancer-specific mortality remain after accounting for clinical characteristics, treatment, and access-to-care-related factors.

Individuals diagnosed with rectal cancer between 2011 and 2020 were identified using the Surveillance, Epidemiology, and End Results Database. The cumulative incidence of rectal cancer-specific mortality was computed. Sub-distribution hazard ratios (sdHRs) and 95% confidence intervals (CIs) for rectal cancer-specific mortality associated with race/ethnicity were estimated using Fine and Gray model with stepwise adjustments for clinical characteristics, treatment modalities, and factors related to access-to-care.

Among 54,370 patients, non-Hispanic (NH) Black individuals exhibited the highest cumulative incidence of rectal cancer-specific mortality (39%), followed by American Indian/Alaska Native (AI/AN) (35%), Hispanics (32%), NH-White (31%), and Asian/Pacific Islander (API) (30%). After adjusting for clinical characteristics, NH-Black patients had a 28% increased risk of rectal cancer mortality (sdHR, 1.28; 95% CI: 1.20-1.35) compared to NH-White patients. In contrast, mortality disparities between Hispanic-White, AI/AN-White, and API-White groups were not significant. The Black-White mortality differences persisted even after adjustments for treatment and access-to-care-related factors. In stratified analyses, among patients with a median household income below $59,999, AI/AN patients showed higher mortality than NH-Whites when adjusted for clinical characteristics (sdHR, 1.32; 95% CI: 1.03-1.70).

Overall, the racial/ethnic disparities in rectal cancer-specific mortality were largely attributable to differences in clinical characteristics, treatment modalities, and factors related to access-to-care. These findings emphasize the critical need for equitable healthcare to effectively address and reduce the significant racial/ethnic disparities in rectal cancer outcomes.