Robert P. Hasserjian¹

¹Department of Pathology, Massachusetts General Hospital, Boston, MA, USA

 

Acute myeloid leukemia (AML) is an aggressive myeloid neoplasm originating from mutated hematopoietic stem cells, which displays arrested maturation resulting in an accumulation of myeloid blasts in the bone marrow and blood.  AML is highly heterogeneous in terms of its biology and clinical behavior, due in large part to the varied portfolios of mutations that in combination drive myeloid proliferation and arrested maturation.  The updated classifications of AML put forth in 2022--the International Consensus Classification (ICC) and 5^th edition World Health Organization Classification (WHO5)--recognize this diversity through several distinct disease groups and specific entities within AML. Many of these entities are defined by a single recurrent genetic driver, while another large group of AML bears one or more gene mutations or cytogenetic aberrations that are strongly associated with myelodysplastic syndromes (MDS). TP53 mutation defines a major subgroup of AML in the ICC that is highly resistant to current therapies.  Accurate diagnosis of classification of AML according to the new ICC and WHO5 schemes requires correctly identifying and enumerating blasts or blast equivalents as well as correctly interpreting genetic testing results.

 

References:

 

1.     Weinberg OK, Porwit A, Orazi A, Hasserjian RP, Foucar K, Duncavage EJ, Arber DA. The International Consensus Classification of acute myeloid leukemia. Virchows Arch. 2023 Jan;482(1):27-37.

2.     Chandra DJ, Lachowiez CA, Loghavi S. Practical considerations in clinical application of WHO 5th and ICC classification schemes for acute myeloid leukemia. Blood Rev. 2024 Mar;64:101156.