The management of chondrosarcoma of bone.

Chondrosarcomas of bone are among the most difficult problems in diagnosis and management in the field of orthopaedic oncology. In addition to the variability of presentation of the "standard" hyaline, myxoid or fibrous types of lesion, three unusual forms of the tumor are now recognized--mesenchymal, clear cell and dedifferentiated--which show differences in their biologic behavior. Chondrosarcomas, with only rare exception, are radio-resistant and show only a limited response to adjunctive chemotherapy. The optimal therapy at present is surgical, but clearly the type of surgical procedure selected should vary with the malignity and extent of the tumor in order to avoid either undertreatment (resulting in a high rate of local recurrence and/or distant metastases) or excessive and unnecessary sacrifice of normal tissue. Patients suspected of having chondrosarcomas should be thoroughly evaluated by clinical examination, radiographic and special studies to define as fully as possible the site and extent of the local tumor, the presence or absence of a soft-tissue mass and the existence of distant metastases. A biopsy should be performed through an incision which can be subsequently excised during the definition procedure. The tissue obtained should be graded histologically and the clinical and radiologic data added to define whether the lesion is benign or a low-grade or high-grade chondrosarcoma. Using a special system recently described by Enneking and Spanier, the lesions should be evaluated on the basis of the grade (G1 or G2); the site of the lesion in relation to the anatomic compartments (T1 or T2) and the presence or absence of distant metastasis (M0 or M1). Based on a scheme presented in this article, the appropriate one of four grades of surgical procedures should be chosen. For benign tumors, Grade I procedures (intralesional curettage or excision) are generally adequate. For Stage IA tumors, occasionally a Grade II procedure, marginal excision may be sufficient, but more frequently Grade III procedures (wide intracompartmental resections) are indicated. Stage IIA and IIB lesions should be treated with Grade III or Grade IV (radical resection) surgical procedures. The treatment of inoperable or Stage IV tumors (those with metastasis) is unsatisfactory and consists of palliative resections, radiation therapy and chemotherapy.