ADJUVANT CHEMOTHERAPY FOR NONMETASTATIC OSTEOSARCOMA OF THE EXTREMITIES IN 2 NEW-ZEALAND CANCER CENTERS

Background: Adjuvant chemotherapy significantly improves survival of patients with nonmetastatic osteosarcoma but most of the data come from trials conducted in major international cancer centres. Aim: To review the efficacy and toxicity of an adjuvant chemotherapy regimen used in two regional cancer centres in New Zealand. Methods: Retrospective review of patients treated for non-metastatic high-grade osteosarcoma of the extremities. The regimen (POMA) consists of high-dose methotrexate 8 g/m(2) and vincristine 1.5 mg/m(2) (maximum 2 mg) on days 1 and 8 followed by folinic acid then doxorubicin 50 mg/m(2) and cisplatin 100 mg/m(2) on day 15. This cycle was repeated every 35 days. Following amputation patients received six cycles while in selected patients two cycles were planned prior to limb salvage surgery followed by a further four cycles. Actuarial survival was calculated using the Kaplan-Meier method. Results: Twenty patients were treated with POMA between 1986 and 1993. Amputation was performed in 16 patients and limb-salvage surgery in four. Sixteen patients (80%) remain alive with no evidence of disease at a median follow-up of 40 months. Thirteen patients (65%) have been continuously disease-free. Actuarial survival at five years is 70%. Seven patients relapsed, six in lungs, of whom four underwent pulmonary metastasectomy; three of these remain free of disease 31, 35 and 40 months later. There was no local relapse. The toxicity of POMA is significant but tolerable. Conclusion: The results obtained at two regional cancer centres in New Zealand using POMA compare favourably to those achieved in clinical trials performed at major international cancer centres.