BCR and acute myeloid leukemia: In summary, this revision of the WHO classification (completed by leading experts), maintains the blast threshold at 20% for the diagnosis of the majority of AML subtypes, but decreases it to ≥10% blasts in BM or blood in the presence of recurrent genetic abnormalities (except for AML with t(9;22)(q34.1;q11.2)/BCR::ABL1) (Table 1) [24,39].