Any acute myeloid leukemia that has the chromosomal anomaly FLT3 internal tandem duplication. (A genetic abnormality that arises from duplications of the juxtamembrane portion of the gene and results in constitutive activation of the FLT3 receptor tyrosine kinase protein in early hematopoietic progenitor cells. It is associated with acute myelogenous leukemia where it appears to correlate with a poor prognosis.). The disease is MONDO_0100415 (acute myeloid leukemia, FLT3 internal tandem duplication). Also known as: AML, Activating FLT3-ITD Gene Mutation, AML, Activating FLT3-ITD Mutation, AML, FLT3 ITD, AML, FLT3 internal tandem duplication, AML, FLT3-ITD, AML, FLT3-ITD Activating Mutation, AML, FLT3-ITD Mutation, AML, FLT3/ITD Mutation.