Outcomes of unrelated cord blood transplants and allogeneic-related hematopoietic stem cell transplants in children with high-risk acute lymphocytic leukemia.

Acute lymphocytic leukemia (ALL) is a common indication for hematopoietic stem cell transplantation (HSCT) in children. Use of unrelated cord blood (UCB) has become increasingly popular as a stem cell source, given the rapid availability and decreased GVHD potential. Publications describing outcomes of children with leukemia who underwent UCB transplants have compared them to those having received unrelated donor marrow transplants. Results are similar. We compared our outcomes using UCB vs allogeneic-related hematopoietic stem cells in pediatric ALL patients since 1992. A total of 49 patients were analyzed. All patients were either in CR1 with high-risk features (n=21) or in CR2 (n=28) with initial remission less than 36 months. Patients received myeloablation with fractionated total body irradiation, cyclophosphamide, and etoposide and GVHD prophylaxis with cyclosporine and methotrexate. Antithymocyte globulin was added for UCB recipients to address the HLA differences. In all, 23 patients underwent allogeneic -related HSCT and 26 underwent UCB transplantation. Other than increased time to engraftment for UCB recipients, results are equivalent. The 3-year overall survival is 64% and 3-year event-free survival is 60% for both groups. Rates of GVHD and transplant-related mortality are also equivalent. UCB is a reasonable option for children with ALL who are referred for HSCT.