Focal irregularity of the rectal mucosa

Mucosal irregularity seen on air-contrast barium enema may be the only radiographic manifestation of a variety of pathologic conditions of the rectum. Seven patients are described to illustrate the fact that when the rectal mucosal irregularity is focal and well demarcated, neoplastic conditions should head the list of diagnostic possibilities. Adenocarcinoma, verrucose carcinoma, adenomatous hyperplasia, villous adenoma, and metastatic carcinoma can all be manifested in this way. The appearance of these lesions on air-contrast barium enema is contrasted with the diffuse mucosal irregularity characteristic of inflammatory and other rectal conditions.