A COMPARISON OF 2 SHORT INTENSIVE ADJUVANT CHEMOTHERAPY REGIMENS IN OPERABLE OSTEOSARCOMA OF LIMBS IN CHILDREN AND YOUNG-ADULTS - THE 1ST STUDY OF THE EUROPEAN OSTEOSARCOMA INTERGROUP

Purpose: A randomized pilot study was undertaken to assess the acute and chronic toxicities of two short intensive chemotherapy regimens, and to evaluate the feasibility of conservative surgery in this setting. Additional aims were to determine the clinical and radiologic response and the degree of histologic necrosis after chemotherapy. With extension of the study, eventual accrual was sufficient to compare disease-free survival (DFS) and overall survival (OS). Patients and Methods: Between July 1983 and December 1986, the European Osteosarcoma Intergroup (EOI) entered 198 eligible patients with classic high-grade extremity osteosarcoma onto a randomized trial that compared doxorubicin (DOX) 25 mg/m2/d times three, intravenous (IV) bolus plus cisplatin (CDDP) 100 mg/m2, 24 hour infusion, every 3 weeks times six; the same combination was preceded 10 days earlier by high-dose methotrexate (HDMTX) 8 g/m2, 6-hour infusion, every 4.5 weeks times four. In the majority of patients (179), chemotherapy was commenced after biopsy; definitive surgery was scheduled at 9 weeks in both groups. Results: Toxicities for both regimens did not differ substantially from those that occurred in other trials of adjuvant chemotherapy in osteosarcoma. Local recurrence (9%) and surgical complications (18%) after conservative surgery were acceptable. With a median follow-up of 53 months, DFS at 5 years is superior (P = .02) for DOX/CDDP, 57% versus 41%, although OS, 64% versus 50%, is not different significantly (P = .10). In a subset of 66 patients for whom pathologic data on the resected specimen were available, DFS (P = .003) and OS (P = .008) were better for those who demonstrated ≥ 90% necrosis. Conclusion: A brief intensive chemotherapy regimen of DOX/CDDP has produced excellent long-term results, which are similar to those that have been achieved in cooperative group studies of longer, more complex multiagent chemotherapy, and provide the basis for a direct comparison in the next EOI study.