Intensive chemotherapy including cisplatin with or without etoposide for children with soft-tissue sarcomas

Forty-two children, 6 months to 17 years of age with newly diagnosed soft-tissue sarcomas (gross residual or metastatic), were treated according to either of two pilot protocols that included intensive chemotherapy before irradiation. Vincristine, actinomycin D, cyclophosphamide, and doxorubicin were used in various combinations with cisplatin alone (regimen 35) or with cisplatin plus etoposide (regimen 36) in a 20-week induction treatment; irradiation (4,000 cGy) was delayed until week 6. Fourteen (82%) of the 17 patients on regimen 35 and 15 (60%) of the 25 on regimen 36 had a complete response. Although severe leukopenia was frequent in both groups (88% and 84% of patients), there were only two fatal infections and no early deaths. Other potentially serious toxicity included a greater than 10% weight loss in 52% of the patients and hypomagnesemia in 74%. An average of 75-100% of the prescribed drug doses were administered during the induction phase of therapy. We conclude that this intensified treatment is toxic but feasible to deliver. The higher overall response rate compared to that in the preceding Intergroup Rhabdomyosarcoma Study (69% vs 53%) suggests improved therapeutic efficacy that warrants further evaluation of both regimens.