Primary malignant fibrous histiocytoma of the ileum: report of a case.

We report herein a case of primary malignant fibrous histiocytoma (MFH) of the ileum. A 71-year-old Japanese man was admitted to our hospital with symptoms of abdominal pain and anorexia. Computed tomography, magnetic resonance imaging, a follow-through study of the small intestine, and angiography all demonstrated a tumor of the ileum suggestive of a primary malignancy. A partial resection of the ileum was performed. It was histopathologically and immunohistochemically diagnosed to be a storiform-type primary MFH of the ileum with peritoneal dissemination. There have been a total of 25 cases of primary small bowel MFH documented in the Japanese or Western literature including our case. The malignant potential of such tumors is high, and the prognosis tends to be very poor. Unfortunately, we could not conclude whether the poor outcome was due to a delayed diagnosis or instead to its biological malignant behavior, since the number of such reported cases is still too small to make any definitive conclusions.