Table 1.

Myeloid neoplasms with germ line predisposition, AML and related precursor neoplasms, and acute leukemias of ambiguous lineage (WHO 2016)

Myeloid neoplasms with germ line predisposition (see Table 2)
AML and related neoplasms	AML and related neoplasms (cont'd)
AML with recurrent genetic abnormalities	Acute myelomonocytic leukemia
AML with t(8;21)(q22;q22.1); RUNX1-RUNX1T1	Acute monoblastic/monocytic leukemia
AML with inv(16)(p13.1q22) or t(16;16)(p13.1;q22); CBFB-MYH11	Pure erythroid leukemia#
Acute promyelocytic leukemia with PML-RARA*	Acute megakaryoblastic leukemia
AML with t(9;11)(p21.3;q23.3); MLLT3-KMT2A†	Acute basophilic leukemia
AML with t(6;9)(p23;q34.1); DEK-NUP214	Acute panmyelosis with myelofibrosis
AML with inv(3)(q21.3q26.2) or t(3;3)(q21.3;q26.2); GATA2,MECOM(EVI1)	Myeloid sarcoma
AML (megakaryoblastic) with t(1;22)(p13.3;q13.3); RBM15-MKL1‡	Myeloid proliferations related to Down syndrome
Provisional entity: AML with BCR-ABL1	Transient abnormal myelopoiesis
AML with mutated NPM1§	Myeloid leukemia associated with Down syndrome
AML with biallelic mutations of CEBPA§	Blastic plasmacytoid dendritic cell neoplasm
Provisional entity: AML with mutated RUNX1	Acute leukemias of ambiguous lineage
AML with myelodysplasia-related changes||	Acute undifferentiated leukemia
Therapy-related myeloid neoplasms¶	MPAL with t(9;22)(q34.1;q11.2); BCR-ABL1**
AML, NOS	MPAL with t(v;11q23.3); KMT2A rearranged
AML with minimal differentiation	MPAL, B/myeloid, NOS
AML without maturation	MPAL, T/myeloid, NOS
AML with maturation

For a diagnosis of AML, a marrow blast count of ≥20% is required, except for AML with the recurrent genetic abnormalities t(15;17), t(8;21), inv(16), or t(16;16). Adapted from Arber et al.³

MPAL, mixed phenotype acute leukemia; NK, natural killer.

^*Other recurring translocations involving RARA should be reported accordingly: for example, AML with t(11;17)(q23;q12); ZBTB16-RARA; AML with t(11;17)(q13;q12); NUMA1-RARA; AML with t(5;17)(q35;q12); NPM1-RARA; or AML with STAT5B-RARA (the latter having a normal chromosome 17 on conventional cytogenetic analysis).

^†Other translocations involving KMT2A (MLL) should be reported accordingly: for example, AML with t(6;11)(q27;q23.3); MLLT4-KMT2A; AML with t(11;19)(q23.3;p13.3); KMT2A-MLLT1; AML with t(11;19)(q23.3;p13.1); KMT2A-ELL; AML with t(10;11)(p12;q23.3); MLLT10-KMT2A.

^‡Rare leukemia most commonly occurring in infants.

^§Diagnosis is made irrespective of the presence or absence of multilineage dysplasia.

^||At least 20% (≥20%) blood or marrow blasts AND any of the following: previous history of MDS or MDS/MPN; myelodysplasia-related cytogenetic abnormality (see list below); multilineage dysplasia; AND absence of both prior cytotoxic therapy for unrelated disease and aforementioned recurring genetic abnormalities. Cytogenetic abnormalities sufficient to diagnose AML with myelodysplasia-related changes are: Complex karyotype (defined as 3 or more chromosomal abnormalities in the absence of 1 of the WHO-designated recurring translocations or inversions, that is, t(8;21), inv(16) or t(16;16), t(9;11), t(v;11)(v;q23.3), t(6;9), inv(3) or t(3;3); AML with BCR-ABL1); Unbalanced abnormalities: −7 or del(7q); −5 or del(5q); i(17q) or t(17p); −13 or del(13q); del(11q); del(12p) or t(12p); idic(X)(q13); Balanced abnormalities: t(11;16)(q23.3;p13.3); t(3;21)(q26.2;q22.1); t(1;3)(p36.3;q21.2); t(2;11)(p21;q23.3); t(5;12)(q32;p13.2); t(5;7)(q32;q11.2); t(5;17)(q32;p13.2); t(5;10)(q32;q21.2); t(3;5)(q25.3;q35.1).

^¶Cases should be classified with the related genetic abnormality given in the diagnosis.

^#The former subgroup of acute erythroid leukemia, erythroid/myeloid type (≥50% bone marrow erythroid precursors and ≥20% myeloblasts among nonerythroid cells) was removed; myeloblasts are now always counted as percentage of total marrow cells. The remaining subcategory AML, NOS, pure erythroid leukemia requires the presence of >80% immature erythroid precursors with ≥30% proerythroblasts.

^**BCR-ABL1⁺ leukemia may present as MPAL; treatment should include a tyrosine kinase inhibitor.