G-CSF producing malignant fibrous histiocytoma in the jejunum: a case report.

Malignant fibrous histiocytoma arising from the alimentary tract is extremely rare. We experienced a young patient with an inflammatory type of malignant fibrous histiocytoma in the jejunum which produced granulocyte-colony stimulating factor. A 16-year-old male was admitted to Umehara Hospital with abdominal pain, frequent vomiting of 2 days' duration, high fever and leukocytosis. Serum level of granulocyte-colony stimulating factor was 61.2 pg/mL. Plain abdominal X-ray, ultrasonography and computed tomography led to the diagnosis of intussusception with small intestinal tumor. On the 2nd hospital day, the patient underwent exploratory laparotomy. The jejunum showed intussusception with a hen's egg-sized tumor. After manual reduction, a 20-cm segment of the jejunum was removed. The patient was alive and doing well 29 months after the operation. Microscopic examination of the resected tumor disclosed an inflammatory type of malignant fibrous histiocytoma in the jejunum, and immunohistochemistry was positive for granulocyte-colony stimulating factor. This is the 5th case of malignant fibrous histiocytoma arising from the small intestine that has been described in the English literature.