To examine the risk of high-risk adenomas (HRA) at third colonoscopy stratified by findings on two previous examinations in a prospective screening colonoscopy cohort of US Veterans with a negative second examination, participants were identified who had three or more colonoscopies from CSP No. 380. The risk of HRA on the third examination, based on findings from the previous two examinations were evaluated. Multivariate logistic regression was used to adjust for multiple covariates. HRA was found at the third examination in 114 (12.8%) of 891 participants.
Those with HRA on both previous examinations had the greatest incidence of HRA at third examination (14/56 – 25%). Compared with those with no adenomas on both previous examinations, participants with HRA on first examination remained at significantly increased risk for HRA at the third examination at 3 years after a negative second examination (OR 3.41), 5 years (OR 3.14), and 7 years (OR 2.89).
In a screened population, HRA on the first examination identified individuals who remained at increased risk for HRA at the third examination, even after a negative second examination, supporting current colorectal cancer surveillance guidelines, which suggest a shortened, 5-year time interval to third colonoscopy after a negative second examination if high-risk findings were present on the baseline examination.
Sullivan, B., Redding, T., Hauser, E., et al. “HighRisk Adenomas at Screening Colonoscopy Remain Predictive of Future High-Risk Adenomas, Despite an Intervening Negative Colonoscopy.” American Journal of Gastroenterology, 2020; Vol. 115, pp. 1275-1282.