Practice-Based Learning to Predict Polyp Histology at Colonoscopy: A Demonstration Project in Community Practice

A) Study Purpose and Rationale Most polyps removed at colonoscopy are small. The natural history of these polyps is not understood completely, but the risk of subsequent cancer in persons with small rectosigmoid adenomas may not be higher than in persons without rectosigmoid adenomas [1]. With improvements in colonoscopic imaging, experienced endoscopists can detect polyps in a large fraction of patients. Removal of all small polyps followed by formal histopathological examination increases the costs associated with colorectal cancer screening, and may increase the risk of complications, depending on the technique that is used for polypectomy.

New technologies such as narrowband imaging (NBI) offer the possibility of in vivo differentiation between adenomatous and hyperplastic polyps. Policies to leave in place small polyps that appear to be hyperplastic, or to remove and discard small polyps after in vivo histologic categorization without formal histopathology review could significantly decrease the costs and potentially the risks of screening and surveillance colonoscopy.

Multiple studies have demonstrated the ability of experienced endoscopists to achieve high accuracy in differentiating adenomatous from hyperplastic polyps using NBI [2, 3, 4, 5]. The level of confidence associated with in vivo histologic categorization of a particular polyp is a valuable adjunct measure in determining subsequent clinical management. Dissemination to the community setting of policies that promote in vivo histologic categorization is likely to require practice-based learning.

B) Hypotheses The investigators hypothesize that community-based endoscopists can learn to identify polyp histology at colonoscopy with the aid of NBI through the use of an introductory didactic program, followed by practice based-learning, and that representative learning curves can be generated that can serve as guidelines for wider dissemination.

C) Purpose The purpose of this study is to test an educational program combining a didactic program followed by practice-based learning that is designed to allow community-based endoscopists to become proficient at in vivo histologic characterization of small polyps with the aid of NBI. This study will not require any changes in endoscopists' decisions regarding the indications and methods for polypectomy.