Acute myeloid leukemia

Acute leukemia of myeloid origin. Peripheral blood, tissue and/or bone marrow show increased number of myeloblasts (typically greater than 20% in the peripheral blood &/or bone marrow). Based on WHO-2008 criteria AMLs are divided into 1) AMLs with recurrent cytogenetic abnormalities (which typically have a better prognosis than the other AMLs) such as APL with t(15;17), AML with t(8;21), AML with t(16;16) or inv (16). 2) AML with Myelodysplasia-related changes (usually have a poor prognosis). 3) Therapy-Related AMLs (usually have a poor prognosis) and 4) AML-NOS which can be minimally differentiated, granulocytic origin (e.g. AML-M2), monocytic or myelomonocytic origin (AML-M4 & M5), erythroid origin (AML-M6) , or megakaryocytic origin (AML-M7). The prognosis on AML-NOS group is variable. Note: A blast with Auer rod(s) is by definition a myeloblast. Myeloblasts with auer rod(s) have been noted in some AML-NOS (e.g. M2) and many times noted in APL.