Efficacy of hypomethylating therapy prior to allogeneic hematopoietic stem cell transplantation upon clinical outcomes in patients with juvenile myelomonocytic leukemia

Abstract

Allogeneic hematopoietic stem cell transplantation (HSCT) remains the only curative therapy for patients with juvenile myelomonocytic leukemia (JMML). The optimal pre-transplantation therapy with maximum efficacy and minimal toxic complications remains a matter of debate. This retrospective study demonstrates single center experience of pre-transplant therapy by hypomethylating agent in children with JMML. Overall, 33 patients were included in analysis. Improved outcome was observed in patients that received pre-transplant AML-like therapy+hypomethylating agents (HMA), AML-like therapy, low-dose chemotherapy ±HMA, only HMA (OS=83%, 44%, 43%, 0%). We have demonstrated that loss of heterozygosity (LoH) of HLA is an important determinant of sensitivity to adoptive immunotherapy and indication for second allo-HSCT.