FLT3 and acute promyelocytic leukemia: So far, this concept has been successful by using all-trans retinoic acid (ATRA) and/or arsenic trioxide in the therapy of acute promyelocytic leukemia (APL) [14], as well as by introducing midostaurin and enasidenib in the therapy of AML with FLT3 and IDH2 mutations, respectively [15, 16].