ARM II: (MAPIE; weeks 12-40) Patients receive doxorubicin IV continuously over 48 hours on days 1-2 in weeks 12, 20, 28, and 36 and cisplatin IV over 4 hours on days 1 and 2 in weeks 12 and 28. Patients also receive high-dose MTX IV over 4 hours on day 1 in weeks 15, 19, 23, 27, 31, 35, 39, and 40. Patients receive ifosfamide IV over 4 hours on days 1-5 in weeks 16, 24, and 32 and on days 1-3 in weeks 20 and 36 and etoposide IV over 1 hour on days 1-5 in weeks 16, 24, and 32.