Judith E. Baars1, Ernst J. Kuipers1, Herman van Dekken2 and C. Janneke van der Woude1 1Department of Gastroenterology and Hepatology, Erasmus MC, Rotterdam, The Netherlands. 2Department of Pathology, ...Erasmus MC, Rotterdam, The Netherlands. Abstract We describe a patient with CrohnâTMs disease who presented with a persistent enterocutaneous fistula. Colonoscopy showed no abnormalities in the terminal ileum and cecum. The patient was treated with corticosteroids and azathioprine for CrohnâTMs disease. The fistula responded partially to therapy. Surgery was performed and revealed a well-differentiated adenocarcinoma, originating from the fistulous tract. In persistent enterocutaneous fistulae surgery is indicated and could keep us from shocking surprises.