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Malignant giant-cell tumours of bone. Clinico-pathological types and prognosis: a review of 29 cases.

Twenty-nine patients with malignant giant-cell tumours of bone (GCT) were followed-up for between 6 months and 18 years. Seventeen of the tumours were primary and 12 were due to malignant degeneration of initially benign lesions. The clinical features did not differ from those of benign GCT, except for a higher incidence in the distal tibia and sacrum. Anaplastic GCTs were included in the study because their clinical and radiographic features and prognosis were no different from those of the GCT grade III of Jaffe. Eighteen of the tumours were grade III, and 11 were anaplastic. This retrospective study was intended to assess the effects of chemotherapy and surgery for malignant GCT. Three treatment groups were selected, in which treatment was either by surgery alone, surgery plus chemotherapy, or radiotherapy alone.--The prognosis was poor and the 5 year tumour-free survival rate in the series was 50%. The prognosis was the same for primary as for secondarily malignant tumours. There was no statistical difference in survival between malignant grade III and anaplastic malignant tumours. The one-year survival rate for patients treated by chemotherapy and surgery was statistically higher (chi2 test) than for persons treated by surgery alone. However, the five-year survival rate and the actuarial survival curves were not statistically different in the two groups (log rank test).--Chemotherapy appears to be of some value in the treatment of these malignant tumours but a larger series is required to confirm the efficacy of this approach.