Aim: Patients with non-advanced adenoma (NAA) underwent surveillance colonoscopy at intervals shorter than the interval recommended by the guidelines. We aimed to assess the incidence of recurrent advanced adenoma (AA) over a 5-year period and to identify risk factors for recurrence.
Method: Patients with and without NAA identified at baseline colonoscopy who had had at least two colonoscopy examinations during the subsequent 5 years were included in the study. Data on the patients' demographics and colorectal findings were extracted from a specially designed colonoscopy database. The primary outcome was the finding of recurrent AA formation. Multivariate analysis was used to identify factors that predict subsequent AA formation at surveillance colonoscopy.
Results: Among 43 155 colonoscopy procedures, 828 cases were identified with NAA (374) and without an adenoma (454). Forty-eight (51.1%) of 94 received a follow-up colonoscopy within 1 year due to an inadequate baseline colonoscopy. Patients with NAA at baseline had a low incidence of AA at an interval of 1-5 years which was not statistically different from patients without adenoma formation at the initial baseline colonoscopy (1.5% vs 2.2%, P = 0.51). The incidence of AA at follow-up colonoscopy performed at 1-3 years and 3-5 years in patients with a baseline NAA was 1.7% and 1.4% (P = 0.59). Age over 50 years and male gender were independent risk factors for AA recurrence within 5 years.
Conclusion: Surveillance colonoscopy within 5 years is of little benefit to patients who had an adequate polypectomy of an NAA at baseline. Too frequent reexamination due to concerns about AA recurrence should be avoided.
Keywords: Colorectal adenoma; colonoscopy; polypectomy; surveillance.
Colorectal Disease © 2015 The Association of Coloproctology of Great Britain and Ireland.