Osteosarcoma of the extremity metastatic at presentation: results achieved in 26 patients treated with combined therapy (primary chemotherapy followed by simultaneous resection of the primary and metastatic lesions).

From September 1986 to December 1989, 26 selected patients with high-grade osteosarcoma of the extremities metastatic at presentation were treated with primary chemotherapy (high doses of methotrexate, -cisplatinum and adriamycin) followed by surgery. Twenty-one cases underwent resections of the primary and metastatic tumor at the same time; owing to the disappearance of lung metastases after preoperative chemotherapy in 3 cases, only the primary tumor was operated on. Due to progression of the disease in 2 patients, no surgery was performed. Histologic examination of the resected specimen was performed to evaluate the percentage of necrosis produced by chemotherapy on the primary and metastatic tumor. After surgery, the patients received further chemotherapy with the same drugs used preoperatively plus ifosfamide and VP-16. The histologic response of the primary tumor was good (> 90% tumor necrosis) in 25% of the cases; in the resected metastatic nodules, 23% had good responses. A discrepancy between the histologic response of the primary and secondary tumor was observed in only 15% of the cases. These results seem to confirm the validity of the strategy (widely used today in the neoadjuvant treatment of non-metastatic osteosarcoma) of changing the postoperative treatment when the histologic response of the primary tumor is poor. At an average follow-up of 3.5 years, only 6 patients remained disease-free; 19 patients relapsed and 1 patient died for adriamycin cardiotoxicity. Of the 19 relapsed patients, 16 died and 3 are still alive but with uncontrolled disease. These results are much worse than those obtained in 144 cases of non-metastatic osteosarcoma of the extremities treated in the same period with the same preoperative chemotherapy (77% with good response in the primary tumor and 78% with continuous disease-free survival). The data suggest that a very effective neoadjuvant chemotherapy for nonmetastatic osteosarcoma of the extremities gives disappointing results in osteosarcoma of the extremities which is metastatic at presentation.