C-kit, a tyrosine kinase receptor, is expressed on most myeloid blasts and is thought to be important in the pathogenesis of AML. Activation of the c-kit receptor leads to phosphorylation and activation of downstream signaling proteins, which are important for cell survival and proliferation. Here, we discuss the prognostic impact of c-kit intensity, measured using the mean fluorescent index (MFI) in patients with newly diagnosed AML. On multivariate analysis, c-kit MFI>20.3 correlated with a decreased progression-free survival and overall survival, independent of known prognostic factors (age, white blood count at diagnosis and cytogenetics). Whether inhibiting c-kit in patients with AML will alter prognosis is the basis of ongoing clinical trials.