Objectives: Colonoscopy surveillance interval data longer than 5 years are limited. We examined adenoma yield to identify factors that predict appropriate intervals for postpolypectomy surveillance greater than 5 years, including risk of advanced adenoma recurrence.
Methods: We identified patients with and without adenomas on an index colonoscopy who returned at 5 to 10 years for a follow-up colonoscopy. Multivariate logistic regression was used to identify variables that predict finding an adenoma on follow-up colonoscopy.
Results: Three hundred ninety-nine patients were identified with a follow-up colonoscopy at an interval of >5 years. Irrespective of surveillance interval, adenoma incidence occurred in 116 patients (29.1%) with 25 (6%) having advanced adenomas. Patients with nonadvanced adenomas on index colonoscopy had a similar risk of advanced adenoma on follow-up colonoscopy at 5 years versus 6 to 10 years, 5% versus 6.2% (P=0.39). The risk of advanced adenoma at 5 and 6 to 10 years in patients with a negative index colonoscopy was 7% versus 3.6% (P=0.15). Patients with an advanced adenoma at index colonoscopy had the highest rate of advanced adenoma detection at 5 years at 26%. Proximal polyp location (odds ratio 12.4, confidence interval 2.7-56.7) predicted advanced adenoma occurrence at 5 years.
Conclusions: Postpolypectomy colonoscopy intervals can be extended beyond 5 years in patients with nonadvanced adenomas. Our findings also support a rescreening interval of 5 to 10 years in patients with a negative index colonoscopy. Patients with an index advanced adenoma are at highest risk for recurrent advanced adenoma and should have repeat colonoscopy before a 5 years interval.