Malignant fibrous histiocytoma (MFH) was found in the femur of a 28-year-old man who had suffered from chronic osteomyelitis. The patient had undergone surgery for a valgus knee deformity and the procedure was complicated by chronic osteomyelitis which lasted for 12 years. Four months after the onset of painful symptoms related to the occurrence of MFH, gross bone destruction with pathologic fracture and pulmonary metastases were present. The patient died 4 months later. Histopathological and immunohistochemical examinations indicated the diagnosis of MFH.
