A phase II study of cisplatin, ifosfamide and doxorubicin in operable primary, axial skeletal and metastatic osteosarcoma. European Osteosarcoma Intergroup (EOI).

Background: Despite advances in the treatment of primary limb osteosarcoma, the outcome of patients with primary metastatic and axial skeletal disease remains poor. The European Osteosarcoma Intergroup have assessed a combination chemotherapy regimen consisting of ifosfamide (IFOS) 3 g/m2/dl-2, doxorubicin (DOX) 25 mg/m2/dl-3 i.v. bolus and cisplatin (CDDP) 100 mg/m2/dl.

Patients And Methods: One hundred nine previously untreated patients with primary osteosarcoma were registered. Eligibility was confirmed in 103. At presentation, 45 eligible patients had metastatic disease, 15 axial skeletal primary tumours and 43 non-metastatic limb tumours.

Results: The major toxicities were myelosuppression (90%, grade 3 or 4) and nausea and vomiting (74%, grade 3 or 4). Overall mean relative dose intensity (RDI) was 80% (88% CDDP, 75% IFOS, 81% DOX). Clinical response as measured by reduction in tumour volume occurred in 36% (95% confidence interval (95% CI): 27%-47%) of primary tumours. Response of pulmonary metastases to chemotherapy was seen in 33% (95% CI: 19%-49%). Good histological response (> or = 90% necrosis of the tumour) occurred in 33% (95% CI: 22%-45%) of resected tumours. Five-year survival was 62% in limb-non-metastatic, 41% in axial skeletal and 16% in limb metastatic patients.

Conclusions: This regimen is active in osteosarcoma but does not appear to be more active than the two-drug CDDP-DOX regimen currently recommended by EOI.