G-CSF producing inflammatory malignant fibrous histiocytoma of the duodenum: A case report

Malignant fibrous histiocytoma arising in the intestinal tract is extremely rare. We report a case of granulocyte colony-stimulating factor (G-CSF) producing inflammatory malignant fibrous histiocytoma of the duodenum. A 60-year-old man admitted for an abdominal tumor and leukocytosis was confirmed by abdominal computed tomography (CT) and hypotonic duodenography to have a duodenal tumor. Serum G-CSF was extremely high at 156pg/ml. Gastrointestinal study showed the tumor to consist of soft, multilobulated tissue. We found during surgery that the tumor arose from the second portion of the duodenum and invaded directly to the hepatic flexure in the colon. Following pancreaticoduodenectomy and right hemicolectomy, microscopic examination of the tumor disclosed inflammatory malignant fibrous histiocytoma, and immunological histo-chemical G-CSF study showed G-CSF in cytoplasmic lesion of tumor cells. Leukocytosis and elevated serum G-CSF improved within one month of surgery. The patient remains well with no evidence of recurrence at 5 years after surgery. This is the sixth case of inflammatory malignant fibrous histiocytoma arising from the gastrointestinal tract reported in the English literature.