Ileal malignant melanoma causing intussusception: report of a case.

Cutaneous malignant melanoma (MM) often metastasizes to the gastrointestinal (GI) tract; however, primary MM of the small intestine is a controversial diagnosis. We report the case of a 76-year-old woman found to have a primary MM in the ileum. After clinical evaluation, the radiological workup, which included magnetic resonance enteroclysis (MRE), revealed a large polypoid intraluminal tumor. She underwent laparotomy and the lesion was excised. Histological examination of the resected specimen revealed morphological and immunohistochemical characteristics of MM and a detailed postoperative examination failed to identify a primary lesion on the skin, anus, oculus, or any other site. The patient died of brain metastasis 6 months after surgery. According to our review of the literature, this is the first case of primary MM of the small intestine diagnosed with the help of MRE.