Combination of FLT3-ITD allelic ratio, NPM1 mutation, and immunophenotypic markers to modulate outcome prediction in normal karyotype AML undergoing hematopoietic stem cell transplantation

Abstract NPM1 mutation status and allelic ratio (AR) of FLT3-Internal Tandem Duplication (FLT3-ITD) are routinely tested for disease risk stratification in patients with normal karyotype (NK) acute myeloid leukemia (AML); however, the predictive impact of immunophenotypic markers on different NPM1/FLT3 genotypes remains unclear. We performed a retrospective analysis of 423 NK-AML patients sub-classified into groups based on their NPM1/FLT3 genotypes. Allogenic HSCT was performed in 124/423 (29%) patients and was significantly associated with longer event free survival (EFS) and overall survival (OS), except for patients with the favourable genotype defined by mutated NPM1 (NPM1mut) combined with normal FLT3 status (FLT3-ITDneg) or FLT3-ITD AR