FLT3 and acute myeloid leukemia: As the mutational status of the FLT3 gene is an important known prognostic factor in AML, we further evaluated PD-L1 significance in patient subcohorts with the wild-type FLT3 form (FLT3-WT) and with FLT3 internal tandem duplications (FLT3-ITD), which are the most frequent FLT3 mutations, leading to constitutive activity of the kinase.