Ileal adenocarcinoma in Crohn's disease: magnetic resonance enterography features.

Patients with Crohn's disease are at increased risk for small bowel adenocarcinoma. We report herein two cases of Crohn's disease-related ileal adenocarcinoma, which were investigated by means of magnetic resonance (MR)-enterography. Two different patterns were observed. In one case, the tumor presented as long circumferential, asymmetric and heterogeneous thickening of the ileum with visible nodule on free induction echo stimulated acquisition images. In the other case, the malignant lesion presented as a tumor mass of the terminal ileum, extending onto the cecum, and showed restricted diffusion on diffusion-weighted MR imaging. In both cases, the tumors were diagnosed preoperatively. Histopathological analysis after surgical resection confirmed T4N1 poorly differentiated mucinous adenocarcinoma of the ileum in association with findings consistent with active in one case and inactive Crohn's disease in the other case. Our observations suggest that MR-enterography may be a useful imaging test for the detection of small bowel adenocarcinoma in patients with Crohn's disease.