FLT3–ITD-positive AML cases (n = 579) were associated with higher leukocytosis (median 78.8 × 109/L vs. 28.3 × 109/L, p < 0.001) and higher bone marrow blasts (median 61.3% vs. 36.8% p < 0.001) at diagnosis. This evidence concerns the gene FLT3 and acute myeloid leukemia.