FLT3 and acute myeloid leukemia: Clinically, FLT3-ITD mutations frequently occur in AML with normal karyotype, t (6:9), t (15:17), and trisomy 8.5, 6 The presence of FLT3-ITD does not appear to affect the complete remission rates, but it significantly increases the risk of relapse.7 Therefore, expression of FLT3-ITD limits disease-free and overall survival.8 FLT3-ITD mutations occur in frame with duplications of 3–400 base pairs in the juxtamembrane domain, and the length of the ITD correlates with overall survival.9 Thus, inhibition of FLT3 should be beneficial for patients with AML with constitutively active FLT3 mutants.