TOTAL-BODY IRRADIATION AND AUTOLOGOUS BONE-MARROW TRANSPLANT IN THE TREATMENT OF HIGH-RISK EWINGS-SARCOMA AND RHABDOMYOSARCOMA

Purpose: In an effort to improve outcome in patients with metastatic or high-risk localized Ewing's sarcoma family of tumors (ESF) and rhabdomyosarcoma (RMS), we explored the role of consolidation therapy with total-body irradiation (TBI) plus autologous bone marrow transplantation (ABMT). Patients and Methods: Ninety-one patients were entered onto one of three consecutive protocols from 1981 to 1986. Induction therapy consisted of four or five cycles of vincristine, doxorubicin, and cyclophosphamide (VAdriaC); in the earlier series, patients received one or two cycles with dactinomycin instead of doxorubicin; Irradiation of the primary site was used for local control. Patients who attained a complete response (CR) to induction therapy were eligible for consolidation with 8 Gy TBI plus VAdriaC and ABMT. Results: Nineteen patients were ineligible for consolidation after failing to achieve or maintain a CR following induction therapy; all 19 are dead of disease. Seven eligible patients elected to forgo consolidation; three of seven are long-term event-free survivors. Sixty-five patients received consolidation therapy; 20 of 65 are long-term event-free survivors. A local control rate of 83% was achieved using radiation therapy as the primary modality of local control. Patients with metastatic disease at diagnosis fared substantially worse than did patients with localized tumors (6-year event-free survival [EFS] rate, 14% v 38%; two-sided P [P2] = .008). Conclusions: Consolidation of patients with metastatic or high-risk localized pediatric sarcomas with 8 Gy TBI plus ABMT has failed to improve the outcome of this group of patients. Metastatic disease at diagnosis continues to confer the poorest prognosis. New therapeutic strategies are needed to consolidate more effectively the remissions that can be achieved in the majority of these patientsy.