Short- and long-term risk of colorectal adenoma recurrence among whites and blacks

Background: It is unclear whether the higher burden from colorectal cancer among blacks is due to an increased biological susceptibility. Objective: To determine whether non-Hispanic blacks (blacks) have a higher risk of adenoma recurrence than non-Hispanic whites (whites) after removal of colorectal adenoma. Design: Secondary analysis of the Polyp Prevention Trial (PPT) data. Setting: United States. Patients: Patients were 1668 self-identified whites and 153 blacks who completed the 4-year trial. Of these, 688 whites and 55 blacks enrolled in a posttrial, passive Polyp Prevention Trial Continued Follow-up Study (PPT-CFS) and underwent another colonoscopy. Main Outcome Measurements: Recurrence and location of the adenoma and advanced adenoma by race-ethnicity during PPT and cumulative recurrence over a mean follow-up of 8.3 years (range, 4.9-12.4 years) among PPT-CFS enrollees. Results: Blacks had similar risk of recurrence of adenoma (39.2% vs 39.4%; incidence risk ratio [RR] =.98; 95% CI,.80-1.20) and advanced adenoma (8.5% vs 6.4%; RR = 1.18; 95% CI,.68-2.05) as whites at the end of PPT. Recurrence risk did not differ by colon subsite. Among PPT-CFS enrollees, the cumulative recurrence rate over a maximal follow-up period of 12 years was similar for blacks and whites for adenoma (67.3% vs 67.0%; RR = 1.01; 95% CI,.84-1.21) and advanced adenoma (14.5% vs 16.9%; RR = 1.03; 95% CI,.60-1.79). Limitation: There were few blacks in the long-term follow-up study. Conclusions: Adenoma and advanced adenoma recurrence did not differ by race. Our study does not support more frequent surveillance colonoscopies for blacks with a personal history of adenoma as an intervention to reduce colorectal cancer disparity.