Adenocarcinoma in perineal fistulas of Crohn's disease.

Until recently, Crohn's disease has not been regarded as a premalignant lesion, but the increasing number of patients with Crohn's disease in whom adenocarcinoma of the gastrointestinal tract develops strongly suggests that these patients are indeed at a higher risk for carcinoma. These patients are usually young and tend to develop a malignancy in the bypassed ileum or right colon. Patients with such lesions usually have a poor prognosis. Adenocarcinoma arising in perineal fistulas secondary to Crohn's disease has not been reported in English medical literature except for one case published in 1975. In this article, the authors report a second, similar case of Crohn's disease with recurrent perineal fistulas. An infiltrating adenocarcinoma developed in these fistulas, in the anorectal region, and in the left labia. The risk of malignancy should be seriously considered in the management of Crohn's disease, especially in young patients. Because of the risk of adenocarcinoma in these patients, resection rather than bypass is recommended in the surgical management.