What question did this study set out to answer?

This study aims to determine the optimal conditioning regimen for pediatric AML patients undergoing HSCT in second complete remission.

May 22, 2026Open Access

Total Body Irradiation, Busulfan, Fludarabine Conditioning for Pediatric Acute Myeloid Leukemia Patients Treated with Hematopoietic Stem Cell Transplantation in Second Complete Remission

Key Points

This study aims to determine the optimal conditioning regimen for pediatric AML patients undergoing HSCT in second complete remission.
Evaluated 43 pediatric AML patients who underwent myeloablative HSCT from 2009 to 2023.
Compared outcomes of patients receiving TBI/Bu/Flu versus Bu/Flu conditioning regimens.
Reported event-free survival and overall survival at 5-year follow-up.
Estimated 5-year event-free survival (EFS) was 57.5%, with TBI/Bu/Flu group showing 73.0% EFS versus 23.1% for Bu/Flu (p=0.004).
5-year overall survival (OS) was 66.8%, all surviving patients remained disease-free at last follow-up.
No significant difference in EFS between haploidentical family donor and other donor transplants.

Abstract

PurposeThe optimum conditioning regimen for pediatric acute myeloid leukemia (AML) patients who receive allogeneic hematopoietic stem cell transplantation (HSCT) in second complete remission (CR) remains unclear.In this study, we reviewed the outcome of AML patients treated with HSCT in second CR at our institution, focusing on the role of the conditioning regimen on post-transplant survival. Materials and MethodsWe evaluated 43 AML patients who received myeloablative HSCT in second CR at our institution from 2009 to 2023.Thirteen of the patients (30.2%) received conditioning with busulfan and fludarabine (Bu/Flu), while 30 patients (69.8%) were treated with total body irradiation (TBI) 8 Gray combined with Bu and Flu (TBI/Bu/Flu). ResultsThirty-two of the patients received a haploidentical family donor (HFD) transplant (74.4%).Estimated 5-year event-free survival (EFS) was 57.57.6% (24/43), with 5-year cumulative incidence of relapse and non-relapse mortality of 30.77.2% and 11.85.0%respectively.Among risk factors for EFS, only the conditioning regimen was important with patients treated with TBI/Bu/Flu having significantly higher 5-year EFS than those who received Bu/Flu (73.08.2% vs. 23.111.7%,p=0.004).There was no significant difference in 5-year EFS between patients who received HFD transplant, and those treated with transplant from other donors.Estimated 5-year OS was 66.87.3%(28/43), with all 28 surviving patients remaining disease-free at last follow-up. ConclusionA myeloablative TBI/Bu/Flu regimen resulted in 5-year EFS of 73.08.2%,indicating favorable

Bookmark

View Full Paper