Abstract: | Colitis cystica profunda is a rare, benign, non-neoplastic condition which usually presents as a mass in the rectum associated with bloody, mucoid diarrhea. This clinical presentation associated with the microscopic finding of mucus cysts in the submucosa has led to the mistaken diagnosis of adenocarcinoma of the rectum and unnecessarily radical operative procedures. Attention to the completely normal cellular architecture provides the key to the correct diagnosis. Local excision is curative, and there is no propensity to develop malignancy in these patients. Experience with one case is reported, and the medical literature on the subject is reviewed. |