Diagnostic criteria for myelodysplastic syndrome (MDS) entities [5, 6].
| Name | Dysplastic lineages |
Cytopeniasa) | RS (%)b) | BM and PB blasts (%) | Cytogeneticsc) |
|---|---|---|---|---|---|
| MDS-SLD | 1 | 1 or 2 | <15/<5d) | BM <5, PB <1, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS-MLD | 2 or 3 | 1–3 | <15/<5d) | BM <5, PB <1,no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS-RS | |||||
| MDS-RS-SLD | 1 | 1 or 2 | ≥15/≥5d) | BM <5, PB <1,no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS-RS-MLD | 2 or 3 | 1–3 | ≥15/≥5d) | BM <5, PB <1,no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS with isolated del(5q) | 1-3 | 1–2 | None or any | BM <5, PB <1, no Auer rods | del(5q) alone or with 1 additional abnormality except -7 or del(7q) |
| MDS-EB | |||||
| MDS-EB-1 | 0–3 | 1–3 | None or any | BM 5–9 or PB 2–4, no Auer rods | Any |
| MDS-EB-2 | 0–3 | 1–3 | None or any | BM 10–19 or PB 5–19 or Auer rods | Any |
| MDS-U | |||||
| 1% blood blasts | 1–3 | 1–3 | None or any | BM <5, PB=1e), no Auer rods | Any |
| SLD and pancytopenia | 1 | 3 | None or any | BM <5, PB <1,no Auer rods | Any |
| Defining cytogenetic abnormality | 0 | 1–3 | <15f) | BM <5, PB <1,no Auer rods | MDS-defining abnormalityg) |
| Refractory cytopenia of childhood | 1–3 | 1–3 | None | BM <5, PB <2 | Any |
a)Cytopenias defined as hemoglobin concentration <10 g/dL, platelet count <100×109/L, and absolute neutrophil count <1.8×109/L, although MDS can present with mild anemia or thrombocytopenia above these levels; PB monocytes must be <1×109/L. b)Ring sideroblasts as the percentage of marrow erythroid elements. c)Cytogenetics by conventional karyotype analysis. d)If
Abbreviations: BM, bone marrow; EB, excess blasts; MDS-U, MDS, unclassifiable; MLD, multilineage dysplasia; PB, peripheral blood; RS, ring sideroblasts; SLD, single lineage dysplasia.