Table 15

PB and BM findings and cytogenetics of MDS

NameDysplastic lineagesCytopenias*Ring sideroblasts as % of marrow erythroid elementsBM and PB blastsCytogenetics by conventional karyotype analysis
MDS with single lineage dysplasia (MDS-SLD)11 or 2<15%/<5%BM <5%, PB <1%, no Auer rodsAny, unless fulfills all criteria for MDS with isolated del(5q)
MDS with multilineage dysplasia (MDS-MLD)2 or 31-3<15%/<5%BM <5%, PB <1%, no Auer rodsAny, 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)11 or 2≥15%/≥5%BM <5%, PB <1%, no Auer rodsAny, unless fulfills all criteria for MDS with isolated del(5q)
 MDS-RS with multilineage dysplasia (MDS-RS-MLD)2 or 31-3≥15%/≥5%BM <5%, PB <1%, no Auer rodsAny, unless fulfills all criteria for MDS with isolated del(5q)
MDS with isolated del(5q)1-31-2None or anyBM <5%, PB <1%, no Auer rodsdel(5q) alone or with 1 additional abnormality except −7 or del(7q)
MDS with excess blasts (MDS-EB)
 MDS-EB-10-31-3None or anyBM 5%-9% or PB 2%-4%, no Auer rodsAny
 MDS-EB-20-31-3None or anyBM 10%-19% or PB 5%-19% or Auer rodsAny
MDS, unclassifiable (MDS-U)
 with 1% blood blasts1-31-3None or anyBM <5%, PB = 1%, no Auer rodsAny
 with single lineage dysplasia and pancytopenia13None or anyBM <5%, PB <1%, no Auer rodsAny
 based on defining cytogenetic abnormality01-3<15%§BM <5%, PB <1%, no Auer rodsMDS-defining abnormality
Refractory cytopenia of childhood1-31-3NoneBM <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.