Vincristine, Doxorubicin, Cyclophosfamide, Actinomycin D, Ifosfamide, and Etoposide in Adult and Pediatric Patients with Nonmetastatic Ewing Sarcoma. Final Results of a Monoinstitutional Study

AIMS AND BACKGROUND: To investigate a six-drug combination in patients with nonmetastatic Ewing sarcoma, focusing on chemotherapy-induced necrosis and chemotherapy toxicity in adult and pediatric patients. METHODS AND STUDY DESIGN: Alternating cycles of vincristine (1.5 mg/m2), doxorubicin (80 mg/m2) and cyclophosfamide (1200 mg/m2) (weeks 0, 6, 13, 22 and 31), ifosfamide (9 g/m2), vincristine (1.5 mg/m2), and actinomycin D (1.5 mg/m2) (weeks 3, 16, 25 and 34), and ifosfamide (9 g/m2) and etoposide (450 mg/m2) (weeks 9, 19, 28 and 37) were administered. Primary chemotherapy-induced necrosis was graded: G3 (complete necrosis), G2 (microfoci of tumor cells) and G1 (macrofoci of tumor cells). RESULTS: From 1996 to 1999, 50 patients with Ewing sarcoma were enrolled. The median age was 23.5 years (range, 4-56). Chemotherapy-induced necrosis (in 28 patients) was G3 in 36%, G2 in 21% and G1 in 43%. At a median follow-up of 110 months (range, 36-129), 5-year overall survival and event-free survival were 72% and 66%, respectively. According to histologic response, 5-year event-free survival was 90% in G3, 83% in G2, and 42% in G1 (P = 0.02). In adult and pediatric (<18 years) patients, the incidence of G4 leukopenia was 62% and 74%, respectively, with febrile neutropenia in 13% and 21%, respectively. G4 thrombocytopenia occurred in 3% of cycles in adults and in 7% in pediatric patients. Platelet and red blood cell transfusions were required respectively in 1% and 11% of cycles in adults and in 6% and 24% of cycles in pediatric patients. CONCLUSIONS: The six-drug combination can be administered safely in adult and pediatric populations. About 40% of patients have a poor chemotherapy-induced tumor necrosis, leading to poor probability of survival. New strategies are recommended to improve survival of poor responders to the six-drug combination.