Occurrence Of The Jak2 V617f Mutation In The Who Provisional Entity: Myelodysplastic/Myeloproliferative Disease, Unclassifiable-Refractory Anemia With Ringed Sideroblasts Associated With Marked Thrombocytosis

The JAK2/V617F mutation has been noted in essential thrombocytemia. We investigated 19 cases with refractory anemia with ringed sideroblasts (RARS), including three RARS with thrombocytosis ( RARS-T). Only the RARS-T patients showed this mutation. More cases need to be analyzed to determine the prevalence of the JAK2/V617F mutation in RARS-T.