Age and dose of chemotherapy as major prognostic factors in a trial of adjuvant therapy of osteosarcoma combining two alternating drug combinations and early prophylactic lung irradiation. French Bone Tumor Study Group.

From January 1978 to May 1983, 41 patients with primary high-grade osteogenic osteosarcoma of a limb were treated with a combination of intensive chemotherapy and prophylactic lung irradiation (PLI) intercalated between the first two cycles of chemotherapy. The primary tumor was treated according to its size and location by amputation, resection, high-dose radiotherapy, and salvage amputation for a tumor progressing under radiotherapy. Two weeks after surgery or simultaneously with radiotherapy, a three-drug regimen (cycle A) consisting of mitomycin C on day 1, vincristine followed by a 6-hour infusion of methotrexate on day 2 was given. Folinic acid rescue was started 6 hours after the end of the methotrexate infusion. A PLI of 20 G was given from day 10 to 22. On day 28, a four-drug regimen (cycle B) combining doxorubicin on day 1, vincristine on day 2 and dacarbazine with cyclophosphamide on days 3 to 6 was administered. Thereafter, five additional cycles of A and B were administered provided that the absolute number of polymorphonuclear cells and platelets had recovered. When these values were not attained, treatment was delayed until recovery. After a mean follow-up of 60.6 months, 16 patients have developed distant metastases, associated in four cases with local recurrence. Sixteen patients have died: 15 with metastases, one with no evidence of disease (toxic death). The overall survival of the entire group is 66% and the continuously disease-free survival 58% at 5 years. Alopecia, nausea, vomiting, asthenia, anorexia, and infraclinical and reversible impairment of lung ventilatory function were universal. A noticeable hematologic toxicity also was seen. One toxic death occurred after a pulmonary infection. Two patients developed cardiomyopathy. A multiparametic analysis of prognostic factors shows the very significant influence of age on treatment outcome. The continuous disease-free survival among the 17 patients younger than 15 years is 41% compared to 79% in older patients. The prognostic influence of age was independent of other factors. The delay (for more than two cycles) of methotrexate administration was the second independent prognostic factor. These results raise the question of using different protocols of adjuvant chemotherapy for patients younger or older than 15 years in order to optimize the curability/toxicity ratio.