Acute Lymphoblastic Leukemia in Children: Better Transplant Outcomes After Total Body Irradiation-based Conditioning

Abstract

Background/aim: Comparison of transplant outcomes in long-term follow-up of children after total body irradiation (TBI)- or chemotherapy-based conditioning allogeneic hematopoietic cell transplantation (allo-HCT).

Patients and methods: Patients undergoing allo-HCT for Acute lymphoblastic leukemia (ALL) conditioned either with TBI (n=55) or chemotherapy (n=84) were compared. The following transplant outcomes were analyzed: overall survival (OS), event-free survival (EFS), relapse incidence (RI), and graft-versus-host-disease (GVHD)-free-relapse-free survival (GRFS).

Results: All analyzed long-term transplant outcomes were significantly better for patients conditioned with TBI at 2 years after transplant. OS at 2 years was 84% after TBI and 60.5% after chemotherapy-conditioning (p=0.005). Risk factor analysis showed that two factors, TBI-based conditioning and transplant in first remission of ALL, significantly improved OS, EFS, GRFS, and decreased RI.

Conclusion: TBI-based conditioning before allogeneic HCT in children with acute lymphoblastic leukemia provides significantly better transplant outcomes, when compared to chemotherapy-based conditioning.

Keywords: Acute lymphoblastic leukemia; GRFS; GVHD-free-relapse-free survival; children; hematopoietic cell transplantation; total body irradiation.