Summary of World Health Organization AML Classifications3
| Category . | Key features . |
|---|---|
| De novo AML | |
| • AML with defining genetic abnormalities | Defined balanced translocation/inversions and gene mutations (eg, mutated NPM1, biallelic CEBPA, RUNX1::RUNX1T1). Only AML with BCR::ABL1 fusion and AML with CEBPA mutation require ≥20% blast count in PB or BM. |
| • AML defined by differentiation* | ≥20% PB or BM blasts with further subcategories based on morphology, cytochemistry, and immunophenotype |
| Secondary myeloid neoplasms | |
| • AML, myelodysplasia related | ≥20% PB or BM blasts and prior therapy has been excluded with either specific cytogenetic abnormalities or somatic mutations.† This includes patients with known history of MDS or MDS/MPN. |
| • AML, post–cytotoxic therapy (previously therapy-related myeloid neoplasms) | ≥20% PB or BM blasts and patient-developed myeloid neoplasms following cytotoxic therapy |
| • Myeloid neoplasms with germline predisposition | Includes myeloid neoplasms with germline pathologic/likely pathologic mutations in CEPBA, DDX41, TP53, RUNX1, ANKRD26, ETV6, GATA2, SAMD9, SAMD9L, and BLM along with telomere biology disorders, RASopathies, Down syndrome, and bone marrow failure syndromes. Phenotype of AML vs MDS with germline predisposition based on presence or absence of >20% PB or BM blasts, respectively. |
| Category . | Key features . |
|---|---|
| De novo AML | |
| • AML with defining genetic abnormalities | Defined balanced translocation/inversions and gene mutations (eg, mutated NPM1, biallelic CEBPA, RUNX1::RUNX1T1). Only AML with BCR::ABL1 fusion and AML with CEBPA mutation require ≥20% blast count in PB or BM. |
| • AML defined by differentiation* | ≥20% PB or BM blasts with further subcategories based on morphology, cytochemistry, and immunophenotype |
| Secondary myeloid neoplasms | |
| • AML, myelodysplasia related | ≥20% PB or BM blasts and prior therapy has been excluded with either specific cytogenetic abnormalities or somatic mutations.† This includes patients with known history of MDS or MDS/MPN. |
| • AML, post–cytotoxic therapy (previously therapy-related myeloid neoplasms) | ≥20% PB or BM blasts and patient-developed myeloid neoplasms following cytotoxic therapy |
| • Myeloid neoplasms with germline predisposition | Includes myeloid neoplasms with germline pathologic/likely pathologic mutations in CEPBA, DDX41, TP53, RUNX1, ANKRD26, ETV6, GATA2, SAMD9, SAMD9L, and BLM along with telomere biology disorders, RASopathies, Down syndrome, and bone marrow failure syndromes. Phenotype of AML vs MDS with germline predisposition based on presence or absence of >20% PB or BM blasts, respectively. |
AML not otherwise specified is no longer recognized as a category.
Cytogenetic abnormalities include 5q deletion or loss of 5q due to unbalanced translocation; monosomy 7, 7q deletion, or loss of 7q due to unbalanced translocation; 11q deletion; 12p deletion or loss of 12p due to unbalanced translocation; monosomy 13 or 13q deletion; 17p deletion or loss of 17p due to unbalanced translocation; isochromosome 17q; and idic(X)(q13). Molecular somatic mutations include SRSF2, SF3B1, U2AF1, ZRSR2, ASXL1, EZH2, BCOR, and STAG2.
BM, bone marrow; PB, peripheral blood.