[Surgery of primary malignant bone tumors]

The term primary malignant bone tumors covers a diversity of entities. Tumor resection is preferable in most. In some, surgery alone is sufficient, in others therapy will be based on a combined modality concept. Resection plays the essential role in those tumors treated by surgery alone, e.g., primary osseous fibrosarcoma. The combined modality approach in osteosarcomas or Ewing's tumors provides for additional elements of local therapy (radiotherapy) or systemic treatment (chemotherapy). The relevance of surgery for local control varies in these latter diagnoses. In highly malignant osteosarcoma, where wide margin surgery is of utmost importance, only 10-20% of patients will survive longer than 5 years without aggressive systemic chemotherapy. Radiotherapy in these patients is only indicated when "marginal" or "less than marginal" surgery is expected. In terms of efficacy, radiotherapy is inferior to surgery. In disseminated osteosarcoma, a curative treatment approach will also provide for surgical removal of all metastases. Treatment of primary malignant fibrous histiocytoma (MFH) of bone is identical to osteosarcoma therapy. Since radiotherapy appears to be marginally more effective than in osteosarcoma, both modalities of local therapy are used. Systemic chemotherapy adds an additional benefit for improved survival. Therapy for Ewing's tumor also follows a combined modality approach. The introduction of systemic chemotherapy has raised 5-year survival rates from less than 10% to above 60%. The role of surgery is currently subject to debate. At present, the use of surgery or irradiation for local control is tailored to the individual patient's needs.