FLT3 and acute myeloid leukemia: Fms-like tyrosine kinase 3 (FLT3) is one of the most mutated genes in AML, and it can be hit by two different genetic lesions, the internal tandem duplication (ITD) is the most frequent, occurring in almost 25% of cases, and the missense mutations of tyrosine kinase domain (TKD), recurring in 5–10% of cases [9,10,11,12,13].