FLT3 and acute myeloid leukemia: FLT3-ITD—a common pattern of activating mutation that leads to the extension of the juxta-membrane domain of FLT3 tyrosine kinase—and NPM1 mutation have opposite prognostic impacts in AML: NPM1 mutation can be a favorable factor only in the absence of FLT3-ITD, and the presence of NPM1 mutation attenuates the adverse prognostic impact of FLT3-ITD [79].