Total-body irradiation and melphalan is a safe and effective conditioning regimen for autologous bone marrow transplantation in children with acute myeloid leukemia in first remission

Purpose: To evaluate the safety and efficacy of a preparative regimen consi sting of fractionated total-body radiation (9.9 to 12 Gy) and melphalan (14 0 mg/m(2) in a single dose) in children with acute myeloid leukemia in firs t complete remission (CR) given autologous bone marrow transplantation (ABM T). Patients and Methods: Fifty-three children (30 males and 23 females; age ra nge, 1.5 to 18 years) were enrolled onto the study, The median time from fi rst CR to ABMT was 3.5 months (range, 1.4 to 13 months), with 45 patients ( 85%) undergoing transplantation within 6 months from the diagnosis. Forty-f ive patients received in vitro marrow purging with standard-dose mafosfamid e (100 mu g/mL), seven patients were treated with interleukin-2 before marr ow collection, and in the remaining child, the marrow was unmanipulated. Th e median infused cell dose was 1.8 x 10(8)/kg (range, 0.4 to 5.8 x 10(8)/kg ). Results: All patients but one achieved hematopoietic engraftment, with a me dian time to neutrophil recovery of 24 days (range, 11 to 66 days). Treatme nt-related toxicity was moderate and consisted mainly of mycositis, One pat ient died from cytomegalovirus interstitial pneumonia, and one died from pu lmonary hemorrhage. Fourteen patients (26%) relapsed at a median time of 6 months after ABMT (range, 2 to 17 months), with a cumulative relapse probab ility of 29% [95% confidence interval, 16% to 42%). The 5-year Kaplan-Meier estimate of survival for all 53 patients was 78% (range, 65% to 90%), wher eas the overall 5-year disease-free survival was 68% (range, 55% to 81%), w ith a median follow-up duration of 40 months (range, 7 to 130 months). Conclusions: These data suggest that, in our cohort of patients, the combin ation of total-body irradiation and melphalan is safe and associated with g ood antileukemia activity, making ABMT an appealing alternative for postrem ission therapy in children with acute myeloid leukemia in first CR. J Clin Oncol 17:3729-3735, (C) 1999 by American Society of Clinical Oncology.