Comparison of outcomes after HLA-matched unrelated and T-cell-depleted haploidentical hematopoietic stem cell transplantation for children with high-risk acute leukemia

T-cell-depleted HAPLO HSCT is an option to treat children with high-risk acute leukemia lacking an HLA-identical donor. We reviewed the outcome of children with acute leukemia after HAPLO (n=21) and HLA-MUD (n=32) transplantation. The proportion of patients with CR2 was significantly higher in HAPLO transplantation than MUD transplantation. Patients with MUD transplantation were significantly higher ABO incompatible than patients with HAPLO transplantation. There was no difference between the 2 groups in terms of engraftment, aGvHD and cGvHD, VOD, hemorrhagic cystitis, infections, and relapse. The 5-year OS of MUD transplantation and HAPLO transplantation groups was found 65.8% and 71.1%, respectively (log-rank 0.51). The 5-year RFS was 80.7% for MUD transplantation group and 86.9% for HAPLO transplantation group (log-rank 0.48). There was no statistically significant difference between 2 groups according to TRM (25% MUD transplantation vs 16.3% HAPLO transplantation, log-rank 0.48). These data suggest that survival for patients with high-risk acute leukemia after HAPLO transplantation with ex vivo ?(+) T-cell depletion is comparable with MUD transplantation.