Findings on serial surveillance colonoscopy in patients with low-risk polyps on initial colonoscopy

This study describes the prevalence of adenomatous polyps at serial follow-up exams after a colonoscopy finding 1 to 2 small tubular adenomas.

We conducted a retrospective cohort of patients with 1 to 2 small tubular adenomas on an initial colonoscopy who underwent at least 2 additional surveillance examinations. Our primary outcome was any or advanced adenomas on the third colonoscopy.

Eighty-eight patients met inclusion criteria. At the second and third colonoscopy, 31/88 (35.2%) patients and 26/88 (29.6%) patients had at least 1 adenoma, respectively. Among the 28 patients with 1 to 2 small tubular adenomas on colonoscopy no. 2, the prevalence of any adenomas on colonoscopy no. 3 was 39.3% [95% confidence interval (CI): 21.5%-59.4%]. Among the 56 patients without adenomas at colonoscopy no. 2, the prevalence of any and advanced adenomas on colonoscopy no. 3 was 25% (95% CI: 14.4%-38.4%), and 3.6% (95% CI: 0.4%-12.3%), respectively.

In patients with 1-2 small tubular adenomas on initial colonoscopy the prevalence of adenomas and advanced lesions on the third colonoscopy remains high even if no adenomas are found on the second colonoscopy.