Patients under 50 years with an HLA matched donor undergo allogeneic bone marrow transplantation (BMT). Patients receive busulfan IV every 6 hours for a total of 14 doses beginning on day -8 and continuing for 3.5 days. At 24 hours following the last dose of busulfan, patients receive cyclophosphamide IV over 2 hours daily for 2 days. Patients receive allogeneic bone marrow infusion on day 0.