Association between the location of colon polyps at baseline and surveillance colonoscopy: a retrospective study

Introduction: Several factors are used to stratify the probability of polyp recurrence. However, there are no studies correlating the location of the initial polyps and the recurrent ones. The aim of this study was to verify whether the polyp location at the surveillance colonoscopy was correlated with the location of the previously excised polyps at the baseline colonoscopy. Methods: A retrospective study of patients submitted to colonoscopy with presence and excision of all polyps, followed by a surveillance colonoscopy. Polyp location was divided into proximal/distal to splenic flexure and rectum. Characteristics and recurrent rates at the same colon location were also evaluated. Results: Out of the 346 patients who underwent repeated colonoscopy, 268 (77.4%) had at least 1 polyp detected. For all the segments there was an increased risk of recurrent polyps in the same location and it was about four times higher in proximal (OR 3.5; CI 2.1-6.0) and distal colon segments (OR 3.8; CI 2.1-6.8), followed by three times higher in the rectum (OR 2.6; CI 1.5-4.6). No difference was found between the rates of recurrence at the same segment, taking into consideration the polyp morphology, size, polypectomy technique employed and histological classification. Conclusion: There seems to be a significant association between polyp location at baseline and surveillance colonoscopy.