Addressing Racial Disparity in Colorectal Cancer Screening With CT Colonography: Experience in an African-American Cohort

Background: Incidence and mortality from colorectal cancer (CRC) are higher among African Americans where CRC screening rates lag behind non-Hispanic whites. The purpose of this investigation was to evaluate CT colonography (CTC) performance and outcome measures in an African-American cohort.

Materials and methods: This study is an institutional review board-approved and Health Insurance Portability and Accountability Act-compliant study. Retrospective evaluation of the African-American cohort from the Atlanta VA Medical Center (Decatur, Georgia) CTC screening program. Colonoscopy referral rates and histologic diagnoses were evaluated.

Results: CTC studies (n = 2490; mean age, 59.5 years [range, 50-80 years]; 85.5% male; all African American) were performed between 2007 and 2016. The per-patient CTC positive rate was 9.8% for polyps from 6 to 9 mm, 5.4% for polyps from 10 to 29 mm, and 1.3% for masses ≥ 30 mm. Based on CTC findings and patient preference, 13.9% of patients were referred to optical colonoscopy and 2.9% were referred to CTC follow-up. Of patients recommended to undergo colonoscopy, 80.6% completed the procedure and colonic pathology was confirmed in 83.2% thereof. Histologic diagnoses were 221 tubular adenomas (161 6-9 mm; 60 ≥ 10 mm), 59 tubulovillous adenomas/villous adenomas (14 6-9 mm; 45 ≥ 10 mm), 34 hyperplastic-serrated polyps (27 6-9 mm; 7 ≥ 10 mm), 18 adenocarcinomas (all ≥ 10 mm), and 11 adenomas with high-grade dysplasia (all ≥ 10 mm). The per-patient positivity rate for patients who had optical colonoscopy (n = 279) was 71.3% for adenoma, 9.7% for hyperplastic polyp, and 6.1% for adenocarcinoma.

Conclusions: CTC is an effective screening modality for African-American adults and could potentially improve rates of colorectal screening in this underserved population.