The major part is occupied by a large oval nucleus composed of very fine nonaggregated chromatin and possessing 3 or more nucleoli.

The main features that distinguish a myeloblast from a lymphoblast upon microscopic examination are the presence of cytoplasmic granules, the lesser degree of condensation in the nuclear chromatin, and the increased prominence of the nucleoli.

Next in the differentiation sequence is the monoblast and the promyelocyte, which can develop into one of three different precursor cells: the neutrophilic, basophilic or eosinophilic myelocyte.

[3][4] The main clinical features of acute myeloblastic leukemia are caused by failure of hemopoiesis with anemia, hemorrhage and infection as a result.

Sometimes acute myeloblastic leukemia can be initiated by earlier hematologic disorders, like myelodysplastic syndrome, pancytopenia, or hypoplasia of the bone marrow.