Phase II Study of Cyclophosphamide, Doxorubicin, Vincristine, Etoposide, and Ifosfamide, Followed by Resection and Radiotherapy in Patients With Peripheral Primitive Neuroectodermal Tumors or Ewing's Sarcoma

OBJECTIVES: I. Determine the response rate and event-free survival of patients with peripheral primitive neuroectodermal tumors or Ewing's sarcoma treated with cyclophosphamide, doxorubicin, vincristine, etoposide, and ifosfamide, followed by surgery (if feasible) and radiotherapy. II. Determine the response to a uniform treatment regimen in order to clarify whether these disease categories each have a different prognosis. OUTLINE: Patients are stratified according to disease category (primitive neuroectodermal tumor vs Ewing's sarcoma). Patients receive treatment on regimen A as outlined below during courses 1-3 and 6 and regimen B as outlined below during courses 4, 5, and 7 in the absence of disease progression or unacceptable toxicity. Each course lasts 3-4 weeks. Patients without metastatic disease after completion of course 3 undergo complete tumor resection, if feasible. Patients achieving complete response with or without microscopic residual disease after completion of course 7 undergo radiotherapy twice daily, 5 days a week, for 3 weeks. Patients with gross residual disease after completion of course 7 undergo radiotherapy twice daily, 5 days a week, for 3.6 weeks. Regimens A and B are defined below: Regimen A: Patients receive cyclophosphamide IV over 6 hours on days 1 and 2, doxorubicin IV continuously and vincristine IV continuously on days 1-3, and vincristine IV on day 9. Regimen B: Patients receive etoposide IV over 1 hour, followed immediately by ifosfamide IV over 1 hour on days 1-5. Patients are followed monthly for 18 months and then every 6 months for 18 months. PROJECTED ACCRUAL: A maximum of 50 patients (25 per stratum) will be accrued for this study within 5 years.