NPM1 and acute myeloid leukemia: A number of recurrent chromosome rearrangements and point mutations have been described, among them the translocation t(8;21) which gives rise to the acute myeloid leukemia 1—eight-twentyone (AML1-ETO) fusion gene, 11q23 rearrangements involving the mixed lineage leukemia (MLL) gene, nucleoporin 98 (NUP98) fusions, nucleophosmin 1 (NPM1) mutations, and fms related receptor tyrosine kinase 3 internal tandem duplications (FLT3-ITD) [4,5,6,9,10].