A CASE OF INFLAMMATORY MALIGNANT FIBROUS HISTIOCYTOMA OF THE COLON

Primary malignant fibrous histiocytoma seldom occurs in the alimentary tract. This documents a case in which a 50-year-old man presented wit h abdominal fullness and anorexia, together with inflammatory reaction s such as fever, leukocytosis, an elevated erythrocyte sedimentation r ate and positive CRP. Radiologic and endoscopic studies revealed a lar ge mass in the ascending colon. The histology of the resected tumor re vealed inflammatory malignant fibrous histiocytoma, a histologic subty pe which is rare among not only soft tissue fibrous but also as gastro intestinal histiocytomas. The inflammatory reactions disappeared follo wing resection of the tumor. Although we suspected that the tumor prod uced granulocyte colony-stimulating factor because of the slightly ele vated serum level and the characteristics of the tumor histology, an i mmunohistochemical study failed to show the G-CSF production by the tu mor cells.