Allogeneic bone marrow transplantation for childhood leukemia following a busulfan and melphalan preparative regimen

Thirty children with leukemia underwent allogeneic bone marrow transplantation (BMT) following a radiation-free preparative regimen, from July 1988 to January 1996. Twelve males and 18 females, ages 9 months to 15 years (median 8.5 years), received busulfan (BU, 4 mg/kg/day for 4 days by mouth), followed by melphalan (L-PAM, 60-70 mg/m2/day i.v. for 3 days), and infusion of allogeneic marrow from an HLA-matched related donor. Diagnoses included acute myelogenous leukemia (n = 20), acute lymphoblastic leukemia (n = 8) and chronic myelogenous leukemia (n = 2). Twenty-five patients were transplanted in first complete remission (CR), three in second CR, and two patients with chronic myelogenous leukemia in the first chronic phase. Graft-versus-host disease (GVHD) prophylaxis consisted of methotrexate (MTX) alone in 27 patients and short-term MTX and cyclosporin A in three patients. Engraftment was achieved in all patients. Toxicities were mild or moderate. Six patients developed acute GVHD: four had grade I and two had grade II. Chronic GVHD was documented in eight patients. Three patients relapsed. As of September 1997, 27 patients were alive and well at 22-110 months (median 61) of follow-up. The disease-free survival rate at 5 years after BMT was 90%. A regimen consisting of high-dose BU and L-PAM without total body irradiation is useful for conditioning for allogeneic BMT in children with leukemia.