Refractory anemia with ring sideroblasts (RARS) and RARS with thrombocytosis: “2019 Update on Diagnosis, Risk‐stratification, and Management”

Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS), now classified under myelodysplastic syndromes with RS (MDS‐RS) and RARS with thrombocytosis (RARS‐T); now called myelodysplastic/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN‐RS‐T).