FLT3 and acute myeloid leukemia: Clinically, AML-M5 frequently presents with hyperleukocytosis and extramedullary involvement, including in the liver, spleen, lymph nodes, gingiva, skin, eyes, larynx, lung, bladder, meninges, and central nervous system [7], and more FLT3 aberrations were found in patients with AML-M5 than in other subtypes [8].