Objective  To investigate the effect of unrelated cord blood transplantation (UCBT) on the treatment of high-risk childhood and adult acute leukemia.

  Methods  Ten patients with high-risk acute leukemia underwent UCBT. Among the 10 patients, 3 were children and 7 were adults with the median age of 29 years old (11-41 years old). Six patients underwent one-unit cord blood transplantation and four patients underwent two-unit cord blood transplantation. The myeloablative conditioning regimen without antithymocyte globulin (ATG) was adopted. Cytarabine (Ara-C), fludarabine (Flu) or total body irradiation (TBI) was added on the basis of busulfan(Bu) and cyclophosphamide (Cy). Ciclosporin and mycophenolate mofetil were used to prevent graft-versus-host disease (GVHD).

  Results  The transplantation was successful in 8 (80%) patients. The median implant-time of leukocytes was 19 d(14-25 d)and that of platelets was 40 d(33-60 d). Three patients developed acute GVHD and no patient developed chronic GVHD. The median follow-up time was 24 months (1-29 months). Seven patients remained in disease-free survival. Both the 2-year overall survival and disease-free survival rates were 66.7%.

  Conclusions  UCBT is feasible in the treatment of high-risk acute leukemia. UCBT is the preferred option for the high-risk patients without HLA-identical sibling donors, which is characterized by low incidence of GVHD and low recurrence rate. It may make patients with acute leukemia remain long-term survival.