Mutation of the fms-like tyrosine kinase 3 gene consisting of internal tandem duplication (FLT3-ITD), which is one of the most frequent genetic alterations, occurs in 15–35% of adults with acute myeloid leukemia (AML).1, 2 Many studies have reported that the FLT3-ITD mutation strongly contributes to an increased risk of treatment failure and to a poor prognosis.3, 4 Detection of ITD mutations at diagnosis is now a routine clinical practice to provide guidance of optimal treatment for AML patients. Here, FLT3 is linked to acute myeloid leukemia.