Comparable outcome of alternative donor and matched sibling donor hematopoietic stem cell transplant for children with acute lymphoblastic leukemia in first or second remission using alemtuzumab in a myeloablative conditioning regimen.

HLA-matched sibling donor (MSD) stem cell transplantation can cure>60% of pediatric patients with acute lymphoblastic leukemia (ALL), but <30% of patients will have a sibling donor. Alternative donor (AD) transplantation can be curative but has a higher risk of graft-versus-host disease (GVHD). The addition of alemtuzumab (Campath 1-H) to AD transplants produces in vivo T cell depletion, which may reduce the risk for GVHD. We now report the outcome for 83 children with ALL (41 MSD, 42 AD) undergoing stem cell transplantation in first or second complete remission. All patients received myeloablative conditioning, including cyclophosphamide, cytarabine arabinoside, and total-body irradiation, with alemtuzumab administered to AD recipients. GVHD prophylaxis consisted of a calcineurin inhibitor with either short-course methotrexate or prednisone. Disease-free survival (DFS) for MSD recipients was 72.3% (95% confidence interval [CI], 55.4%-83.6%) versus 62.4% (95% CI, 45.2%-75.4%) for AD recipients. The 100-day mortality was 7.1% in the AD group and 2.4% in the MSD group. Relapse rates were identical (24%). Treatment-related mortality, principally viral infection, explained the difference in survival. For children undergoing stem cell transplantation (SCT) from alternative donors, alemtuzumab with a myeloablative conditioning regimen resulted in DFS comparable to MSD.

Comparable outcomes of matched-related and alternative donor stem cell transplantation for pediatric severe aplastic anemia.

Matched sibling donor (MSD) bone marrow transplantation is the treatment of choice for pediatric patients with severe aplastic anemia (SAA); however, only about 33% of patients will have an HLA-identical sibling. Alternative donor (AD) transplants may be an option for these patients, but such therapies have been associated with greater incidence of graft failure and graft-versus-host disease (GVHD). We retrospectively analyzed 36 pediatric patients who received 38 bone marrow or peripheral blood stem cell transplants (15 MSD and 23 AD) for SAA at our institution from April 1997 to October 2005. Nineteen AD recipients received reduced intensity conditioning with cyclophosphamide, low-dose total body irradiation, and antithymocyte globulin (ATG) or Campath. The 4-year overall survival for MSD recipients was 93% versus 89% for AD recipients treated with reduced intensity conditioning regimens at a median follow-up of 52 months (range, 6-99 months). No patient receiving Campath, compared with 3 of 9 patients receiving ATG, developed extensive, chronic GVHD. We conclude that, for children with SAA, AD transplantation is as effective as MSD transplantation. Further, compared with ATG, preparatory regimens containing Campath may be associated with a lower incidence of extensive, chronic GHVD.