Racial and ethnic differences in colon cancer surgery type performed and delayed treatment among people 45 years old and older in the USA between 2007 and 2017: Mediating effect on survival

This study examined the associations of socioeconomic status (SES), race/ethnicity, surgery type, and treatment delays with mortality among colon cancer patients. In addition, the study also quantifies the extent to which clinical and SES factors' variations explain the racial/ethnic differences in overall survival. We studied 111,789 adult patients ≥45 years old who were diagnosed with colon cancer between 2010 and 2017, identified from the Surveillance, Epidemiology, and End Results (SEER) database. We performed logistic regression models to examine the association of SES and race/ethnicity with surgery type and first course of treatment delays. We also performed mediation analysis to quantify the extent to which treatment, sociodemographic and clinicopathologic factors mediated racial/ethnic differences in survival. Non-Hispanic (NH) Blacks [adjusted Odds Ratio (aOR) = 1.19, 95% CI:1.13–1.25] were significantly more likely to undergo subtotal colectomy and to experience treatment delays [aOR = 1.39, 95% CI: 1.31–1.48] compared to NH Whites. Hispanics [aOR = 1.59, 95% CI: 1.49–1.69] were more likely to experience treatment delays than NH Whites. Delayed first course of treatment explained 23.56% and 56.73% of the lower survival among NH Blacks and Hispanics, respectively, compared to their NH White counterparts. Race/ethnicity is significantly associated with the surgery type performed and the first course of treatment delays. Variations in treatment, SES, and clinicopathological factors significantly explained racial disparities in overall mortality. These disparities highlight the need for multidisciplinary interventions to address the treatment and social factors perpetuating racial disparities in colon cancer mortality.