RUNX1 and myelodysplastic syndrome: The International Working Group for the Prognosis of MDS (IWG-PM) has suggested that SF3B1mut MDS as a distinctive entity which has a favorable prognosis with <1% peripheral blood or <5% BM blasts, absence of del (5q), inv (3), abnormal 3q26, monosomy 7, or complex karyotype (CK) and RUNX1 or EZH2 mutations (19).