Polyps are defined as pathologic epithelial elevations of the aerodigestive and genitourinary tracts. This term describes any of the types of abnormal growths identified on or involving the colonic mucosa that protrude into the bowel lumen.
Polyps are of concern to clinicians due to their malignant potential depending on the histologic type of the polyp identified.
The primary histology of colonic polyps includes the following: adenomas, serrated polyps [including hyperplastic polyps and sessile serrated adenomas (SSAs)], hamartomas, and inflammatory polyps.
As some are neoplastic, they are the target of screening modalities (including colonoscopy, computed tomography (CT) colonography) to remove them prior to their malignant degeneration. Other polyp-like lesions, usually submucosal rather than mucosal in nature, such as carcinoids, leiomyomas, and lipomas, will be described and discussed in Chap. 49.