Primary adenocarcinoma in an enterocutaneous fistula associated with Crohn's disease.

Increasing numbers of intestinal adenocarcinomas in patients with Crohn's disease have been reported, but the strength of this association still needs to be elucidated. Adenocarcinoma has also been documented in different types of fistulous tracts associated with Crohn's disease. The first case of well-differentiated mucinous adenocarcinoma involving only enterocutaneous fistulae is reported in a patient with long-standing Crohn's disease complicated by persistent abdominal wall fistulous tracts. The malignant lesion arose from neoplastic transformation of columnar epithelium lining portions of the fistulae occurring as a result of either re-epithelialization of these inflammatory tracts or mural implantation of mucosal tissue secondary to prior ulceration. The patient has remained disease-free eight years after surgical resection of the tumour. Even though intestinal carcinoma is not as strongly associated with Crohn's disease as with ulcerative colitis, intestinal carcinoma should be considered in the setting of long-standing disease, previous intestinal exclusion surgeries and complications such as enterocutaneous or other types of fistulous tracts. The prognosis of such patients may be excellent with early diagnosis and treatment.