Abstract B103: Racial and geographic disparities in stage of presentation in the colorectal cancer hotspot region of North Carolina

Abstract

Abstract Background: Despite improvements in colorectal cancer (CRC) screening, treatment, and long-term outcomes, recent epidemiological studies have demonstrated that geographic disparities in CRC persist. Spatial mapping has identified distinct hotspots of increased CRC death rates, including 11 rural counties in eastern North Carolina (NC). The primary aim of this study was to (1) measure CRC incidence by stage in the NC hotspot and non-hotspot regions, and (2) determine if racial disparities exist in stage-stratified incidence and overall mortality rates by geographic region. Methods: CRC diagnosis and death data from 2008-2016 were obtained from the NC Central Cancer Registry and analyzed by hotspot and non-hotspot regions by summary cancer stage at diagnosis and race. The non-hotspot region was defined as 71 NC counties outside of eastern NC. Death rates (95% CI) were expressed per 100,000 person-years and age-adjusted to the 2000 U.S. standard population. Regional rates were calculated for the 8-year interval. Results: Within the hotspot region in eastern NC, the overall incidence rate of CRC is higher than non-hotspot NC [43.7 (95% CI 39.2-48.8) vs 38.4 (95% CI 37.6-39.2)]. Within the hotspot counties, overall incidence rates are higher among African American (AA) compared to White patients [51.1 (95% CI 43.4-59.9) vs. 39.1 (95% CI 33.6-45.4)], and this disparity persists across all stage categories. The incidence among AA and White patients with localized disease is 18.4 and 14.4, respectively; for regional disease, 16.7 vs. 13.9; and for distant disease, 11.4 and 7.8. Similar racial disparities in CRC incidence are also observed within the non-hotspot counties (localized 16.1 vs. 13.5, regional 15.2 vs. 13.5, and distant 11.3 vs. 7.8). CRC mortality rates in the hotspot counties are higher among both AA and White patients (21.7 and 15.5, respectively) compared to non-hotspot NC (19.1 and 12.8, respectively), although the absolute difference by race is similar (6.2 vs. 6.3, respectively). Conclusions: Patients residing within the 11 rural hotspot counties in NC have higher age-adjusted incidence of localized, regional, and distant CRC and higher mortality rates than patients in non-hotspot counties. Noteworthy racial disparities exist in both stage at presentation and mortality rates; however, absolute racial disparities appear similar in both geographic regions. Future work should investigate the underlying etiology for both increased CRC incidence and mortality among AA and White patients in the NC hotspot counties. Citation Format: Tyler Hinshaw, Suzanne Lea, Justin Arcury, Alexander A Parikh, Rebecca A Snyder. Racial and geographic disparities in stage of presentation in the colorectal cancer hotspot region of North Carolina [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr B103.