Table 2 The latest classification and defining characteristics of MDS [132]

MDS with defining genetic abnormalities

 MDS-5q (MDS with low blasts and isolated 5q deletion)

< 5% BM and < 2% peripheral blood

5q deletion alone, or with one other abnormality other than monosomy 7 or 7q deletion

 MDS-SF3B1 (MDS with low blasts and SF3B1 mutation)

< 5% BM and < 2% peripheral blood

Absence of 5q deletion, monosomy 7, or complex karyotype

SF3B1

 MDS-biTP53 (MDS with biallelic TP53 inactivation)

< 20% BM and peripheral blood

Generally complex

Two or more TP53 mutations, or one mutation with evidence of TP53 copy number loss or copy neutral loss of heterozygosity

MDS, morphologically defined

 MDS-LB (MDS with low blasts)

< 5% BM and < 2% peripheral blood

 MDS-h (hypoplastic MDS)

 MDS-IB (MDS with increased blasts)

 MDS-IB1

5–9% BM or 2–4% peripheral blood

 MDS-IB2

10–19% BM or 5–19%

peripheral blood or Auer rods

5–19% BM; 2–19% peripheral blood