NTRK1 and acute myeloid leukemia: The receptor tyrosine kinase fms-like tyrosine kinase 3 (FLT3) is expressed at high levels on malignant blasts in 70% to 100% of cases of acute myeloid leukemia (AML) [1], [2] and is mutated, most commonly by internal tandem duplication (ITD), in 20 to 30 percent of AML cases in different series [3]–[7].