Busulfan, cyclophosphamide and total body irradiation as conditioning for allogeneic bone marrow transplantation for acute and chronic myeloid leukemia.

Fifty patients with acute myeloid leukemia (AML) or chronic myeloid leukemia (CML) underwent allogeneic bone marrow transplantation between October 1988 and January 1997. Patients received 8 mg/kg of busulfan (BU) with 120 mg/kg of cyclophosphamide (CY) followed by 10 Gy of total body irradiation (TBI). Twenty consecutive patients with AML in first remission (n = 9) or CML, in chronic phase (n = 11) entered the study (group I). Thirty consecutive patients with advanced myeloid malignancies including AML (n = 19) and CML (n = 11) also entered the study (group II). The probability of leukemia-free survival at 5 years was 85% for group I patients and 50% for group II patients. Severe regimen-related toxicities occurred in 16% of patients (two in group I, six in group II). The most common sites affected by severe toxicities were lung (n = 6), liver (n = 2) and heart (n = 2). The relapse rate was higher for patients allografted in advanced stages of disease (O% at 5 years for group I and 28% for group II). These results suggest that BU + CY + TBI is a very effective conditioning regimen in patients with myeloid malignancies.