Malignant fibrous histiocytoma of bone. A clinico-pathologic study of 9 cases.

Nine cases of malignant fibrous histiocytoma of bone from a consecutive unselected 10 years' series of 106 malignant primary bone tumours seen in a tumour center serving a population of about 2 mill. are reported. Five women and four men aged between 31 and 76 years had tumours localized in long bones of extremities (7) and pelvic bones (2). Two cases developed in previously irradiated bones, one in a solitary bone cyst and one in chronic osteomyelitis. All tumours, histologically of high-grade malignancy, were pleomorphic with collagenous, hyalinised areas without conspicuous myxoid components. The histiocytic derivation was proved by enzyme histochemistry in two cases. All patients were treated with ablative surgery without adjuvant chemo- or radiotherapy of the primary tumours. Four patients died within five years from tumour dissemination. The remaining five patients, observed from two to four years, have no signs of local recurrence or metastasis.