Cyclophosphamide in the management of Ewing's sarcoma.

Abstract

The activity of alkylating agents, cyclophosphamide and melphalan, was studied in 13 patients with metastatic Ewing's sarcoma. A total of 15 courses of melphalan was administered to five patients at a dose of 1.0 to 1.5 mg/kg per course. There were no responses. Cyclophosphamide was administered to 11 patients, including three melphalan failures. Five partial and two complete responses were obtained, two of whom were melphalan failures. An intermittent intravenous schedule of 15 mg/kg once weekly was convenient and effective, resulting in five of the seven responses. The direct intrapleural instillation of two doses of 15 mg/kg produced total control of pleural effusion in one patient. Only one of four patients on a daily oral schedule of 5.0 mg/kg demonstrated a partial response. The mean dose to response was 45 mg/kg, and the mean duration of response was 5+ months. Factors adversely affecting responsiveness are short-duration of disease prior to initiation of chemotherapy and a “symptom status” indicating marked disability from disease. Severe vomiting, noted in four of the seven patients receiving parenteral therapy and one of the four on oral therapy, was the most disabling side reaction. Ewing's sarcoma should be considered a cyclophosphamide-responsive neoplasm in the same category as neuroblastoma and malignant lymphoma.