Capizzi II regimen: Course 1: Patients receive cytarabine IV over 3 hours every 12 hours on days 0, 1, 7, and 8 and asparaginase IM on days 1 and 8. Course 2: Patients also receive cytarabine IT or TIT on days 0, 7, and 14.AlBMT regimen: Therapy begins within 2-8 weeks of hematologic recovery. Patients may receive interim therapy consisting of oral thioguanine for about 2 weeks. Patients then receive oral busulfan every 6 hours on days -9 to -6 and cyclophosphamide IV over 1 hour on days -5 to -2. AlBMT is infused over 4 hours beginning 36-48 hours after the last dose of cyclophosphamide. Patients in complete remission after completing the Capizzi II regimen proceed to maintenance therapy on arm III.