World Health Organization (WHO) Classification of Myelodysplastic Syndromes (MDS)/Neoplasms | |||
| NAME | RING SIDEROBLASTS | MYELOBLASTS | KARYOTYPE |
|---|---|---|---|
| MDS with single lineage dysplasia (MDS-SLD) | <15% (<5%)a | BM <5%, PB <1%, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS with multilineage dysplasia (MDS-MLD) | <15% (<5%)a | 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) | ≥15% / ≥5%a | 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) | ≥15% / ≥5%a | BM <5%, PB <1%, no Auer rods | Any, unless fulfills all criteria for MDS with isolated del(5q) |
| MDS with isolated del(5q) | 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 | None or any | BM 5-9% or PB 2-4%, no Auer rods | Any |
| MDS-EB-2 | None or any | BM 10-19% or PB 5-19% or Auer rods | Any |
MDS, unclassifiable (MDS-U) • with 1% blood blasts • with single lineage dysplasia and pancytopenia • based on defining cytogenetic abnormality | None or any None or any 15% | BM <5%, PB=1%, no Auer rods BM <5%, PB=1%, no Auer rods BM <5%, PB=1%, no Auer rods | Any Any MDS-defining abnormality |
MDS, unclassifiable (MDS-U) • with 1% blood blasts • with single lineage dysplasia and pancytopenia • based on defining cytogenetic abnormality | None or any None or any 15% | BM <5%, PB=1%, no Auer rods BM <5%, PB=1%, no Auer rods BM <5%, PB=1%, no Auer rods | Any Any MDS-defining abnormality |
| Refractory cytopenia of childhood | None | BM <5%, PB <2% | Any |