Hematopoietic Stem Cell Transplantation for Children Acute Myeloid Leukemia, a Single Center Experience

Hematopoietic Stem Cell Transplantation (HSCT) plays an important role in the treatment of children with Acute Myeloid Leukemia (AML). Match related donor (MRD) and Unrelated Cord Blood Transplantation (UCBT) for patients who lack a sibling donor are the options of HSCT in our unit. UCB offers the advantage of faster availability of banked cryopreserved UCB units compared with unrelated bone marrow grafts with similar results in survival. We report our results of HSCT for AML. We analyzed 28 children receiving allogeneic HSCT for AML, 17 UCBT and 11 HSCT from a MRD. Cord blood units were selected with 1 or 2 HLA mismatch; reduce intensity conditioning (RIC) in all except two UCBT consists of fludaradine and melphalan. Conditioning for MRD HSCT consists of BU16/Cy120. Graft vs host disease prophylaxis with cyclosporine/MTX for MRD HSCT and cyclosporine/MMF o cyclosporine/methylprednisolone for UCBT. Average for neutrophil recovery in UCBT and MRD HSCT was 21 and 19 days respectively, average for platelet recovery in UCBT and MRD HSCT was 34 and 23 days respectively. Transplant related mortality in UCBT and MRD HSCT 18% and 17% respectively, causes of death were relapse(5=29%) grade IV hepatic graft versus host disease(2) and bacterial sepsis(1) for UCBT, causes of death in MRD HSCT were relapse (1=9%) cerebral infarction(1) and chronic graft versus host disease(1).  With a median follow up of 1 year, overall survival for entire cohort was 60.7%, overall survival for UCBT was 52,9% and 72,7% for MRD HSCT (p=0,25). Despite being few patients these results show no significant difference in overall survival between related donors and unrelated cord blood. RIC with fludarabine and melphalan is a promising alternative in children; it shows an acceptable relapse rate compared with other more toxic conditionings.