Unlike WHO2016, where the myeloblast count was not a significant factor in diagnosing certain AML subtypes, such as AML with t(8;21)(q22;q22.1), AML with inv(16)(p13.1q22) or t(16;16)(p13.1;q22), and acute promyelocytic leukemia (APL) with PML-RARA, WHO2022 now applies myeloblast count criteria to additional genetic abnormalities such as t(9;11)(p21.3;q23.2), t(6;9)(p23;q34.1), inv(3)(q21.3q26.2), t(3;3)(q21.3;q26.2) or t(1;22)(p13.3;q13.1), while excluding AML with BCR::ABL1 fusion and CEBPA mutation. This evidence concerns the gene CEBPA and acute promyelocytic leukemia.