Combination chemotherapy and radiation therapy in the treatment of metastatic osteogenic sarcoma.

Fourteen patients with 16 metastatic ostogenic sarcoma lesions were treated with high-dose methotrexate (HDMTX) with citrovorum factor rescue (CFR), adriamycin, and pulse high-dose cyclophosphamide combined with radiation therapy. Thirteen of 16 lesions responded. Responses consisted of relief of pain (6/6 patients) in bone lesions, roentgenographic and clinical evidence of decrease in the size of the bone lesions (6/7 patients), and a decrease in the size of pulmonary metastases (2/4 patients). The 2 patients whose pulmonary metastases responded to combined therapy developed pulmonary fibrosis and pneumonitis in the treated areas 3 months after radiation therapy (RT) (1400 and 1600 rads respectively). Of two bulky primary tumors that appeared to respond, both were ultimately found to contain viable tumor; a third less bulky primary tumor appeared to respond more completely. Three smaller metastatic bone lesions that were ultimately biopsied showed no evidence of active tumor. It is concluded that: 1) combination therapy (particularly HDMTX and RT) has an additive effect in controlling osteogenic sarcoma bone lesions, but bulky primary tumors cannot be completely eradicated; 2) although synergistic in treating osteogenic sarcoma, combination therapy can produce enhanced toxicity in surrounding normal lung tissue; and 3) combination therapy is of value in the palliative treatment of metastatic lesions other than that of lung, and in the treatment of small primary bone lesions. However, experience to date does not justify the delay in surgical ablation of a primary lesion in a child who presents without metastatic disease.