Excellent Outcomes of Hematopoietic Stem Cell Transplant for Pediatric High Risk and Relapsed Acute Myeloid...

Hematopoietic stem cell transplant (HSCT) remains the cornerstone of treatment in patients with high-risk and relapsed acute myeloid leukemia (AML). In the absence of a fully matched donor, haploidentical HSCT is a feasible option. The aim of this study is to analyze the outcomes of pediatric AML patients, who underwent HSCT at our center.

This was a retrospective analysis of 48 pediatric patients who underwent 50 transplants at our center from January 2014 to December 2024.

Median age at transplant was 8.5 years, and the male-to-female ratio was 1.9:1. Of 48 children, 46 patients had de novo AML, and 2 had secondary AML. Twenty-nine patients underwent matched sibling donor (MSD), 3 underwent matched related donor (MRD) and the remaining 18 received haploidentical HSCT. All patients received Fludarabine-based conditioning regimens and engrafted. Incidence of acute graft versus host disease (GVHD) in matched donor and haploidentical HSCT was 21.8% and 44.4%, respectively ( P =0.09). Incidence of chronic GVHD was 3.1% in matched donor and 5.5% in haploidentical HSCT ( P =0.72). Cumulative incidence of relapse was 16%. Viral reactivations were seen in 17 patients, cytomegalovirus (CMV) being the commonest. At a median follow-up of 40.9 months, EFS and OS of the overall cohort were 78% and 86%, respectively. Nonrelapse mortality (NRM) was 6%. EFS in matched donor and haploidentical HSCT was 78.1% versus 77.8% ( P =0.78). OS in matched donor and haploidentical HSCT was 84.4% versus 88.9% ( P =0.83). GVHD-free relapse-free survival (GRFS) was 58%. Among the factors analyzed, only pretransplant minimal residual disease (MRD) positivity was found to be associated with significantly poor outcome.

HSCT for children with AML from the developing world shows promising outcomes with high survival rates even in the absence of matched donors. Having expertise in multiple specialties, such as a molecular hematologist, infectious disease (ID), and intensive care specialist, can significantly enhance the outcomes for transplant patients.