Risk factors for advanced adenomas amongst small and diminutive colorectal polyps: A prospective monocenter study

Background: The management of colorectal polyps <10 mm in diameter is controversial. Our aim was to evaluate the rate and risk factors for advanced adenomas and high grade neoplasia amongst small (6-9 mm) and diminutive (1-5 mm) colorectal polyps. Methods: Endoscopic and pathological reports of colonoscopies performed in our centre were collected prospectively. Advanced adenoma was defined by presence of a villous component and/or high grade dysplasia; high grade neoplasia by presence of high grade dysplasia and/or intramucosal carcinoma. Results: 1468 patients were included (53.1% male, mean age 59.5 +/- 14 years); 414 polyps <10 mm were detected, 9.9% advanced adenomas and 1.7% high grade neoplasia. Amongst small polyps, 25(35.2%) were advanced adenomas, mainly due to villous features, and 3 (4.2%) were high grade neoplasia. Polyp size was associated with advanced adenomas (odds ratio = 8.47). Conclusion: The rate of advanced adenomas amongst small polyps was 35%, mainly due to the presence of villous features. Polyp size was identified as a risk factor of advanced adenoma amongst polyps <10 mm. Given these results, we believe that polypectomy should be warranted for patients presenting with small polyps at computed tomography colonography. (C) 2011 Editrice Gastroenterologica Italians S.r.l. Published by Elsevier Ltd. All rights reserved.