Primary chemotherapy and delayed surgery for osteosarcoma of the extremities with synchronous metastases.

From September 1986 to September 1989 11 patients affected by osteosarcoma of the extremities with synchronous metastases were treated with two cycles of high-dose methotrexate i.v., cisplatin i.a. and adriamycin i.v. followed by simultaneous resection of the primary and metastatic tumor. A complete histological examination of the resected specimens was always performed to evaluate the percentage of necrosis produced by chemotherapy on both the primary and metastatic tumor. After surgery the patients received 3 more cycles of the same drugs as used preoperatively plus ifosfamide. The histological response of the primary tumor was 'good' (90% or more tumor necrosis) in 4 patients and 'poor' (less than 90% of tumor necrosis) in 7, while in the 34 metastatic nodules the resulting necrosis was good in 8 and poor in 26. A good correlation between the histological response in the primary and metastatic tumor was observed, particularly for poor responders (91% of poor responses also in metastatic nodules). At an average follow-up of 42 months, only 3 patients are alive, 2 disease-free, and one with uncontrolled disease. These data suggest that the prognosis of osteosarcoma of the extremities with synchronous metastases remains poor, even with a very aggressive treatment. Our results also seem to confirm the validity of the present strategy in the treatment of non-metastatic osteosarcoma: introducing new drugs post-operatively in poor responding patients can allow a better treatment of microscopic disease and can improve the prognosis for these patients.