Two genes in which recurrent mutations, which often co-occur, with known clinical significance have been identified in patients with AML include the gene encoding nucleophosmin protein-1 (NPM1) and one of the signalling genes, FMS (Feline McDonough Sarcoma gene)-related tyrosine kinase 3 (FLT3).3,6NPM1 mutations are associated with a favourable prognosis,3 while the FLT3-internal tandem duplication (ITD) mutation is considered an independent poor prognostic factor in patients with AML.7 However, the co-occurrence of these two gene mutations modulates their prognostic impacts.3,7. This evidence concerns the gene CSF1R and acute myeloid leukemia.