Iron overload in myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a group of disorders characterized by ineffective hematopoiesis that leads to peripheral cytopenias. Iron overload results from high transfusion requirements and retrospective studies have shown it to be associated with relatively poor survival in a subset of the low risk patients. Recent discoveries have led to the identification of hepcidin as a key regulator of iron metabolism and to the association of non-transferrin bound iron moieties, such as labile plasma iron, with the end organ damage in iron overload states. Currently, there is limited data in evaluating the role of iron chelators in MDS and data from studies in Thalassemia and hemachromostosis have been used to predict ferritin levels above 1000-2500ng/mL and history of 20 blood transfusions as clinical end points for considering iron chelation in MDS. Deferoxamine and deferasirox, the two iron chelators approved for use in the US, have shown efficacy in reducing iron overload in MDS in retrospective studies are now being evaluated for effects on overall survival in prospective studies. On the basis of retrospective data, it is reasonable to offer iron chelation to the lower risk MDS patients requiring frequent transfusions, while monitoring for specific adverse affects in patients on treatment.