Analysis of colonoscopy surveillance in 5-year follow-up after polypectomy of non-advanced colorectal adenoma

Objective To assess the results of colonoscopy surveillance in 5 years after polypectomy of non-advanced colorectal adenoma and to identify its risk factors. Methods Patients undergoing colonoscopy and followed up with colonoscopy within 5 years between January 2003 and December 2013 were retrospectively analyzed.No substance or only small quantity of clear water left in the intestinal tract and colonoscopes accessing ileocecus were regarded as complete examination. The initial colonoscopy was regarded as the baseline colonoscopy. Patients with non-advanced adenomas were assigned to the case group and those without were to the control group. Data of clinical characteristics and colorectal findings were estimated and risk factors were identified. Results A total of 828 patients were included, 374 patients in the case group and 454 in the control group on baseline colonoscopy.The case group had a low incidence of advanced adenomas at a 1 to 5 years interval when compared with the control group, both with adequate baseline examination. The detection rates of advanced adenomas on follow-up colonoscopy at 1 to 3 years and 3 to 5 years in case group were 1.7%(3/178) and 1.4%(2/148), respectively (P>0.05). Regression analysis showed age≥50 years old and being male were the independent risk factors for advanced adenomas recurrence within 5 years follow-up. No colon cancer was found in 828 patients during the follow-up. Conclusion Surveillance colonoscopy intervals within 5 years is of little benefit to patients who had adequate polypectomy. Too early reexaminations due to concerns about advanced adenomas recurrence can be avoided. Key words: Therapeutic endoscopy; Colonoscopy; Colorectal adenoma; Surveillance interval