Phase II/III trial of etoposide and high-dose ifosfamide in newly diagnosed metastatic osteosarcoma: a pediatric oncology group trial.

PURPOSE: The objectives of this trial were to estimate the response rate, progression-free survival, and overall survival of patients who received therapy with etoposide and high-dose ifosfamide, and to define the toxicity of this combination when provided with standard chemotherapy in patients with newly diagnosed metastatic osteosarcoma.

PATIENTS AND

METHODS

Eligible patients received infusions of 100 mg/m(2) per day of etoposide and 3.5 g/m(2) per day of ifosfamide for 5 days. Therapy with granulocyte colony-stimulating factor was begun on day 6. This was repeated 3 weeks after therapy was begun. Response was determined at week 6 by both standard World Health Organization response criteria and by pathologic determination of tumor necrosis of the primary tumor.

RESULTS

Forty-three patients were registered; 39 were assessable for response and 41 for toxicity and survival. Twenty-eight (68%) of 41 had metastatic sites only in the lung; 12 (29%) had metastatic sites in other bones with or without lung involvement. Four patients (10%) experienced complete response, and 19 patients (49%) experienced partial response, for an overall response rate of 59% +/- 8%. The projected 2-year progression-free survival (PFS) for the 28 patients with metastases to lungs was 39% +/- 11%. The projected 2-year PFS for the 12 patients with metastases to other bones (with or without pulmonary metastases) was 58% +/- 17%. Two patients died as a result of therapy toxicity. Eighty-three percent of patients had grade 4 neutropenia, and 29% had grade 4 thrombocytopenia. Ten patients (24%) had sepsis. Fanconi's syndrome was observed in five patients.

CONCLUSION

The combination of etoposide and high-dose ifosfamide is effective induction chemotherapy for patients with metastatic osteosarcoma, despite significant associated myelosuppression sometimes complicated by infection and renal toxicity.