Myelodysplastic syndromes (MDS) and myelodysplastic syndrome/acute myeloid leukemia (MDS/AML)
| . | Dysplastic lineages . | Cytopenias . | Cytoses* . | BM and PB Blasts . | Cytogenetics† . | Mutations . |
|---|---|---|---|---|---|---|
| MDS with mutated SF3B1 (MDS-SF3B1) | Typically ≥1‡ | ≥1 | 0 | <5% BM <2% PB | Any, except isolated del(5q), −7/del(7q), abn3q26.2, or complex | SF3B1 (≥ 10% VAF), without multi-hit TP53, or RUNX1 |
| MDS with del(5q) [MDS-del(5q)] | Typically ≥1‡ | ≥1 | Thrombocytosis allowed | <5% BM <2% PB§ | del(5q), with up to 1 additional, except −7/del(7q) | Any, except multi-hit TP53 |
| MDS, NOS without dysplasia | 0 | ≥1 | 0 | <5% BM <2% PB§ | −7/del(7q) or complex | Any, except multi-hit TP53 or SF3B1 (≥ 10% VAF) |
| MDS, NOS with single lineage dysplasia | 1 | ≥1 | 0 | <5% BM <2% PB§ | Any, except not meeting criteria for MDS-del(5q) | Any, except multi-hit TP53;not meeting criteria for MDS-SF3B1 |
| MDS, NOS with multilineage dysplasia | ≥2 | ≥1 | 0 | <5% BM <2% PB§ | Any, except not meeting criteria for MDS-del(5q) | Any, except multi-hit TP53,; not meeting criteria for MDS-SF3B1 |
| MDS with excess blasts (MDS-EB) | Typically ≥1‡ | ≥1 | 0 | 5-9% BM, 2-9% PB§ | Any | Any, except multi-hit TP53 |
| MDS/AML | Typically ≥1‡ | ≥1 | 0 | 10-19% BM or PBǁ | Any, except AML-defining¶ | Any, except NPM1, bZIP CEBPA or TP53 |
| . | Dysplastic lineages . | Cytopenias . | Cytoses* . | BM and PB Blasts . | Cytogenetics† . | Mutations . |
|---|---|---|---|---|---|---|
| MDS with mutated SF3B1 (MDS-SF3B1) | Typically ≥1‡ | ≥1 | 0 | <5% BM <2% PB | Any, except isolated del(5q), −7/del(7q), abn3q26.2, or complex | SF3B1 (≥ 10% VAF), without multi-hit TP53, or RUNX1 |
| MDS with del(5q) [MDS-del(5q)] | Typically ≥1‡ | ≥1 | Thrombocytosis allowed | <5% BM <2% PB§ | del(5q), with up to 1 additional, except −7/del(7q) | Any, except multi-hit TP53 |
| MDS, NOS without dysplasia | 0 | ≥1 | 0 | <5% BM <2% PB§ | −7/del(7q) or complex | Any, except multi-hit TP53 or SF3B1 (≥ 10% VAF) |
| MDS, NOS with single lineage dysplasia | 1 | ≥1 | 0 | <5% BM <2% PB§ | Any, except not meeting criteria for MDS-del(5q) | Any, except multi-hit TP53;not meeting criteria for MDS-SF3B1 |
| MDS, NOS with multilineage dysplasia | ≥2 | ≥1 | 0 | <5% BM <2% PB§ | Any, except not meeting criteria for MDS-del(5q) | Any, except multi-hit TP53,; not meeting criteria for MDS-SF3B1 |
| MDS with excess blasts (MDS-EB) | Typically ≥1‡ | ≥1 | 0 | 5-9% BM, 2-9% PB§ | Any | Any, except multi-hit TP53 |
| MDS/AML | Typically ≥1‡ | ≥1 | 0 | 10-19% BM or PBǁ | Any, except AML-defining¶ | Any, except NPM1, bZIP CEBPA or TP53 |
Cytoses: Sustained white blood count ≥ 13 × 109/L, monocytosis (≥0.5 × 109/L and ≥10% of leukocytes) or platelets ≥450 × 109/L; thrombocytosis is allowed in MDS-del(5q) or in any MDS case with inv(3) or t(3;3) cytogenetic abnormality.
BCR::ABL1 rearrangement or any of the rearrangements associated with myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions exclude a diagnosis of MDS, even in the context of cytopenia.
Although dysplasia is typically present in these entities, it is not required.
Although 2% PB blasts mandates classification of an MDS case as MDS-EB, the presence of 1% PB blasts confirmed on 2 separate occasions also qualifies for MDS-EB.
For pediatric patients (<18 y), the blast thresholds for MDS-EB are 5% to 19% in BM and 2% to 19% in PB, and the entity MDS/AML does not apply.
AML-defining cytogenetics are listed in the AML section.