Two staging systems are commonly used for acute myeloid leukemia (AML). The French-American-British (FAB) classification system is based on morphology to define specific immunotypes. The World Health Organization (WHO) classification reviews chromosome translocations and evidence of dysplasia.[1]
Table. FAB classification of AML (Open Table in a new window)
FAB subtype |
Name |
Adult AML patients (%) |
M0 |
Undifferentiated acute myeloblastic leukemia |
5% |
M1 |
Acute myeloblastic leukemia with minimal maturation |
15% |
M2 |
Acute myeloblastic leukemia with maturation |
25% |
M3 |
Acute promyelocytic leukemia |
10% |
M4 |
Acute myelomonocytic leukemia |
20% |
M4eos |
Acute myelomonocytic leukemia with eosinophilia |
5% |
M5 |
Acute monocytic leukemia |
10% |
M6 |
Acute erythroid leukemia |
5% |
M7 |
Acute megakaryocytic leukemia |
5% |
AML with recurrent genetic abnormalities[2, 3] :
AML, not otherwise specified (NOS):
Myeloid sarcoma
Myeloid proliferations related to Down syndrome:
Blastic plasmacytoid dendritic cell neoplasm