We explored the combination of busulfan/cyclophosphamide/etoposide as conditioning regimen prior to bone marrow transplantation in 31 patients with acute myeloid leukemia (AML) in first complete remission. The preparative regimen consisted of 16 mg/kg busulfan, 30-60 mg/kg VP-16, and 120 mg/kg cyclophosphamide. With a median follow-up of 30.5 months (range, 5-60 months), 25 patients are alive in continuous complete remission. Estimated disease-free survival at 5 years is 80.5%. Death was due to transplant-related toxicity (graft-versus-host disease and cytomegalovirus infection, graft-versus-host disease and pneumonia, sepsis and mucositis, respectively). None of the patients have relapsed. As demonstrated by the results of this analysis, the conditioning regimen busulfan/cyclophosphamide/etoposide is effective and well tolerated in patients with AML in first complete remission. Main nonhematological toxicities were mucositis and hepatotoxicity. The low mortality and relapse rate appears to justify allogeneic bone marrow transplantation for patients with AML in first complete remission who have an HLA-identical donor. Whether this regimen offers a substantial improvement in disease-free and overall survival over presently used regimens warrants further investigation.
