Figure 1.
Hierarchical classification of the International Consensus Classification of AML.
The classification is hierarchical (ie, AML with recurrent genetic
abnormalities takes precedence over all other categories); among the
remaining categories, AML with mutated TP53 supersedes AML with
myelodysplasia-related gene mutations, and the latter supersedes AML
with myelodysplasia-related cytogenetic abnormalities. aMyeloblasts,
monoblasts, and megakaryoblasts are included in the blast count.
Monoblasts and promonocytes, but not abnormal monocytes, are counted as
blast equivalents in AML with monocytic or myelomonocytic
differentiation, and promyelocytes in the setting of PML::RARA or variant RARA
rearrangement. Cases with prior diagnosis of MPN are excluded and are
classified as accelerated (10%-19% blasts) or blast phase (≥20% blasts)
MPN. For patients who already have a history of MDS/MPN (eg, CMML), the
diagnosis of MDS/MPN should be retained until there are ≥20%
blasts/blast equivalents; however, once an AML-defining recurrent
genetic abnormality (eg, KMT2A rearrangement or NPM1 mutation) is detected and the blast count is ≥10%, AML-type therapy is recommended. bAML-defining recurrent genetic abnormalities are t(15;17)(q24.1;q21.2)/PML::RARA; t(8;21)(q22;q22.1)/RUNX1::RUNX1T1; inv(16)(p13.1q22) or t(16;16)(p13.1;q22)/CBFB::MYH11; t(9;11)(p21.3;q23.3)/MLLT3::KMT2A; t(6;9)(p22.3;q34.1)/DEK::NUP214; inv(3)(q21.3q26.2) or t(3;3)(q21.3;q26.2)/GATA2, MECOM(EVI1); mutated NPM1; in-frame bZIP mutated CEBPA; t(9;22)(q34.1;q11.2)/BCR::ABL1; other recurrent rearrangements involving RARA, KMT2A, MECOM, and other rare rearrangements as listed in Table 1. The entity is named with the specific genetic abnormality. Cases with BCR::ABL1
rearrangement and 10% to 19% blasts are classified as CML in
accelerated phase, and cases with history of CML and ≥20% blasts are
classified as CML in myeloid blast phase. cExamples how to
append diagnostic qualifiers: AML with myelodysplasia-related
cytogenetic abnormality, therapy-related; AML with
myelodysplasia-related gene mutation, prior myelodysplastic syndrome;
AML with myelodysplasia-related gene mutation, germline RUNX1 mutation (ie, gene or syndrome should be specified).