[Diagnosis and treatment of malignant bone fibrohistiocytoma]

Malignant fibrous histiocytoma (MFH) and giant cells sarcoma arise from fibrous tissue and histiocytic cells evenly distributed in all age group, except children much less common than osteosarcoma and chondrosarcoma. They most commonly localize in the major long bones (femur, tibia, humerus) and in pelvis. Pain and sometimes swelling are the most frequent symptoms but pathologic fractures are rather common. Medical imaging shows a purely osteolytic tumor centrally or eccentrically located, ill defined with a permeative or even moth eaten patterns. Periosteal reaction is scarce or absent. Osteogenic reaction or tumor calcifications are absent. Outcome was historically better than those of osteosarcoma but hangs on the grading of tumors; low grade sarcoma have a regional evolution while high grade malignant histiocytofibroma are threatened with metastases. Therapy must be adapted to the histological grading and the extent of the illness. Low grade localized MFH are best treated by wide resection. High grade MFH are preferentially treated by a comprehensive multidisciplinary approach with preoperative chemotherapy including high dose methotrexate, wide resection and postoperative chemotherapy. With such a treatment, nearly 80% of patients seen with localized tumor of the limb can be cured and keep a functional limb.