PB and BM findings and cytogenetics of MDS
| Name . | Dysplastic lineages . | Cytopenias* . | Ring sideroblasts as % of marrow erythroid elements . | BM and PB blasts . | Cytogenetics by conventional karyotype analysis . |
|---|---|---|---|---|---|
| MDS with single lineage dysplasia (MDS-SLD) | 1 | 1 or 2 | <15%/<5%† | BM <5%, PB <1%, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS with multilineage dysplasia (MDS-MLD) | 2 or 3 | 1-3 | <15%/<5%† | BM <5%, PB <1%, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS with ring sideroblasts (MDS-RS) | |||||
| MDS-RS with single lineage dysplasia (MDS-RS-SLD) | 1 | 1 or 2 | ≥15%/≥5%† | BM <5%, PB <1%, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS-RS with multilineage dysplasia (MDS-RS-MLD) | 2 or 3 | 1-3 | ≥15%/≥5%† | 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 with excess blasts (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, unclassifiable (MDS-U) | |||||
| with 1% blood blasts | 1-3 | 1-3 | None or any | BM <5%, PB = 1%,‡ no Auer rods | Any |
| with single lineage dysplasia and pancytopenia | 1 | 3 | None or any | BM <5%, PB <1%, no Auer rods | Any |
| based on defining cytogenetic abnormality | 0 | 1-3 | <15%§ | BM <5%, PB <1%, no Auer rods | MDS-defining abnormality |
| Refractory cytopenia of childhood | 1-3 | 1-3 | None | BM <5%, PB <2% | Any |
| Name . | Dysplastic lineages . | Cytopenias* . | Ring sideroblasts as % of marrow erythroid elements . | BM and PB blasts . | Cytogenetics by conventional karyotype analysis . |
|---|---|---|---|---|---|
| MDS with single lineage dysplasia (MDS-SLD) | 1 | 1 or 2 | <15%/<5%† | BM <5%, PB <1%, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS with multilineage dysplasia (MDS-MLD) | 2 or 3 | 1-3 | <15%/<5%† | BM <5%, PB <1%, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS with ring sideroblasts (MDS-RS) | |||||
| MDS-RS with single lineage dysplasia (MDS-RS-SLD) | 1 | 1 or 2 | ≥15%/≥5%† | BM <5%, PB <1%, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS-RS with multilineage dysplasia (MDS-RS-MLD) | 2 or 3 | 1-3 | ≥15%/≥5%† | 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 with excess blasts (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, unclassifiable (MDS-U) | |||||
| with 1% blood blasts | 1-3 | 1-3 | None or any | BM <5%, PB = 1%,‡ no Auer rods | Any |
| with single lineage dysplasia and pancytopenia | 1 | 3 | None or any | BM <5%, PB <1%, no Auer rods | Any |
| based on defining cytogenetic abnormality | 0 | 1-3 | <15%§ | BM <5%, PB <1%, no Auer rods | MDS-defining abnormality |
| Refractory cytopenia of childhood | 1-3 | 1-3 | None | BM <5%, PB <2% | Any |
Cytopenias defined as: hemoglobin, <10 g/dL; platelet count, <100 × 109/L; and absolute neutrophil count, <1.8 × 109/L. Rarely, MDS may present with mild anemia or thrombocytopenia above these levels. PB monocytes must be <1 × 109/L
If SF3B1 mutation is present.
One percent PB blasts must be recorded on at least 2 separate occasions.
Cases with ≥15% ring sideroblasts by definition have significant erythroid dysplasia, and are classified as MDS-RS-SLD.