Problematic Colorectal Polyps

Two issues commonly arise for pathologists reporting adenomatous polyps of the colorectum. Particularly problematic within large sigmoid colonic adenomas is the distinction between benign misplacement of epithelium into the submucosa and invasive malignancy. This distinction requires careful morphologic evaluation of key discriminatory features, assisted only rarely by the application of selected adjunctive immunohistochemistry. Following a diagnosis of adenocarcinoma within a polypectomy or other local excision specimen, systematic assessment is required of features that may indicate the risk of residual local and/or nodal neoplastic disease and inform management decision-making regarding the need for further endoscopic or surgical intervention.