High-definition colonoscopy and risk factors for recurrence of advanced adenomas in patients with a personal history of polyps

Abstract

Postpolypectomy surveillance is one of the most common reasons for performing colonoscopy. Our purpose was to assess characteristics of basal adenomas related to the recurrence of advanced adenomas, and to compare the patterns observed in recurrent adenomas with the use of conventional colonoscopy (CC) (1995-1998 period) or high-definition colonoscopy (HDC) (2005-2008 period). Analyses were based on 612 patients with recurrent adenomas (n=306) or no adenomas (control group; n=306), with at least two follow-up colonoscopies. A total of 56 patients with recurrent adenomas during the 1995-1998 period were compared with 116 patients in the 2005-2008 period. Morphology, size, location, and pathological diagnosis of each polyp were recorded. Multiple logistic regressions were used to calculate relative risk (RR) for recurrence. The study population was predominantly male (68.8%), with a mean age of 61.1 years and a mean follow-up period of 90.6±59.4 months. Advanced adenomas were found during follow-up evaluation in 120 patients (39.2%). The RR of advanced adenoma recurrence was 1.64 [95% confidence interval (CI): 1.01-2.64] among patients with baseline high-risk adenoma and 0.61 (CI: 0.38-0.98) among those with baseline low-risk adenoma. In the multivariable analyses, patients with larger adenomas were more likely to develop advanced recurrence (RR 1.02; 95% CI: 1.01-1.04). Both techniques (CC and HDC) detected a similar number (2.37±3.28 vs. 3.11±4.63; P=0.406) at qualifying colonoscopy. During follow-up both periods showed comparable adenoma characteristics. Patients with larger adenomas were more likely to develop advanced recurrence. HDC did not detect significantly more adenomas than CC. Characteristics of recurrent adenomas were comparable in both periods.