Haploidentical hematopoietic stem cell transplantation without in vitro T cell depletion for treatment of hematological malignancies in children

To investigate the efficacy and safety of haploidentical (from family member donors) hematopoietic stem cell transplantation (HSCT) for children. 42 children under 14 yrs old with hematological malignancies underwent haploidentical HSCT. Outcomes were analyzed. Thirty-three children were classified as high-risk candidates. Of 42 patient/donor pairs, 4 (9.5%) were mismatched in 2 HLA loci, 15 (35.7%) in 3 loci, and 23 (54.8%) in 4 loci. Follow-ups were performed for a median of 1110 (449-1959) days after transplantation. All patients achieved stable engraftments. The cumulative incidence of acute graft-versus-host disease (aGVHD) of grade 2-4 was 57.2%, and that of grade 3-4 was 13.8%. The cumulative incidence of chronic graft-versus-host disease (cGVHD) was 56.7% for total and 29.5% for extensive. Twenty-seven patients survived with a 3-yr probability of leukemia-free survival (LFS), 57.3±8%, 18 of them were in the high-risk group. Fifteen patients died, 4 from infection, 7 from relapse of leukemia, 2 from heart failure, one from severe aGVHD, and one from lymphoproliferative disorders. The results encourage extending haploidentical HSCT without T cell depletion treatments to children with an indication for transplantation.