OBJECTIVES: I. Assess the value of idarubicin added to the standard conditioning regimen of allogeneic and autologous stem cell transplantation in patients with leukemia or myelodysplastic syndrome at high risk of relapse. II. Determine time to recovery of polymorphonuclear neutrophil leukocyte (PMN) and platelet counts in these patients. III. Evaluate the rate and type of grade 3-4 toxicity, particularly mucositis, and the number of days with fever in these patients. IV. Determine the incidence of acute and chronic graft versus host disease (GVHD) in these patients.

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to disease (acute myelogenous leukemia (AML) vs acute lymphocytic leukemia (ALL) or lymphoblastic leukemia (LL) vs myelodysplastic syndrome (MDS) or secondary AML vs chronic myelogenous leukemia (CML) vs non-Hodgkin's lymphoma vs multiple myeloma), stage of disease (if not CML, 1st complete response (CR) vs 2nd CR vs no 1st/2nd CR; if CML, 1st CR vs other phases), conditioning regimen (cyclophosphamide (CTX) and total body irradiation (TBI) vs busulfan (BU) and CTX vs other), source of donor (allogeneic vs autologous), T-cell depletion or autologous transplantation (no vs yes), and source of stem cells (bone marrow vs peripheral blood stem cell). Patients are randomized to receive a standard regimen or an intensified regimen. Standard pretransplant treatment: CTX on days -6 and -5 and TBI on days -4 through -2, or BU on days -8 through -5 and CTX on days -4 and -3, or BU on days -8 through -5 and melphalan IV on day -4. Intensified pretransplant regimens: I. Continuous infusion of idarubicin (IDA) over 48 hours on days -12 and -11, followed 5 days later with CTX on days -6 and -5 and TBI on days -4 to -2 II. IDA followed 5 days later with BU on days -8 through -5, and then CTX on days -4 and -3 III. IDA followed by BU on days -8 through -5 and melphalan IV on day -4. Stem cells are infused on day 0. Patients are followed every 3 months during the first 3 years, then every 6 months thereafter.

PROJECTED ACCRUAL: A total of 207 patients will be accrued for this study within 3 years.