Cronkhite-Canada syndrome associated with a rectal cancer and adenomatous changes in colonic polyps.

A 52-year-old man with the clinical features of Cronkhite-Canada syndrome developed rectal cancer. Radiologic and endoscopic examinations revealed gastrointestinal polyposis. Histologic examination of the biopsied polyps showed cystic dilatation of glands with an inflammatory stroma. A later biopsy from a rectal polyp proved to be an adenocarcinoma. The totally resected colon and upper rectum had an ulcerated rectal cancer and numerous polyps; most of the polyps showed histological changes typical of the syndrome. Only three polyps had adenomatous changes at their surfaces. Adenomatous and carcinomatous changes of epithelia can occur in non-neoplastic polyposis of Cronkhite-Canada syndrome from which presumably a carcinoma can develop, as in the present case.