Supportive care and chelation therapy in MDS: are we saving lives or just lowering iron?
The myelodysplastic syndromes (MDS) are characterized by cytopenias and risk of transformation to acute myeloid leukemia (AML). Although new treatments are available, a mainstay in MDS remains supportive care, which aims to minimize the impact of cytopenias and transfusion of blood products. Red blood cell (RBC) transfusions place patients at risk of iron overload (IOL). In beta-thalassemia major (BTM), IOL from chronic RBC transfusions inevitably leads to organ dysfunction and death. With iron chelation therapy (ICT), survival in BTM improved from the second decade to near normal and correlated with ICT compliance. Effects of ICT in BTM include reversal of cardiac arrhythmias, improvement in left ventricular ejection fraction, arrest of hepatic fibrosis, and reduction of glucose intolerance. It is not clear whether these specific outcomes are applicable to MDS. Although retrospective, recent studies in MDS suggest an adverse effect of transfusion dependence and IOL on survival and AML transformation, and that lowering iron minimizes this impact. These data raise important points that warrant further study. ICT is potentially toxic and cumbersome, is costly, and in MDS patients should be initiated only after weighing potential risks against benefits until further data are available to better justify its use. Since most MDS patients eventually require RBC transfusions, the public health implications both of transfusion dependence and ICT in MDS are considerable. This paper summarizes the impact of cytopenias in MDS and treatment approaches to minimize their impact, with a focus on RBC transfusions and their complications, particularly with respect to iron overload.
Leitch
Heather A
HA
Division of Hematology, St. Paul's Hospital and the University of British Columbia, Vancouver, BC, Canada. hleitch@providencehematology.com
Vickars
Linda M
LM
D000368:Aged; D000740:Anemia / Q000209:etiology / Q000628:therapy; D001565:Benzoates / Q000627:therapeutic use; D016913:Blood Component Transfusion / Q000009:adverse effects / Q000191:economics; D015913:Chelation Therapy; D003131:Combined Modality Therapy; D003676:Deferoxamine / Q000627:therapeutic use; D016298:Hematopoietic Cell Growth Factors / Q000627:therapeutic use; D006801:Humans; D006834:Hydrazines / Q000627:therapeutic use; D007501:Iron; D007502:Iron Chelating Agents / Q000627:therapeutic use*; D019190:Iron Overload / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology / Q000628:therapy; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000150:complications* / Q000188:drug therapy / Q000401:mortality / Q000628:therapy; D009503:Neutropenia / Q000209:etiology / Q000628:therapy; D056687:Off-Label Use; D018962:Phlebotomy; D017410:Practice Guidelines as Topic; D011720:Pyrazoles / Q000627:therapeutic use; D011961:Receptors, Fc / Q000627:therapeutic use; D011993:Recombinant Fusion Proteins / Q000627:therapeutic use; D013921:Thrombocytopenia / Q000209:etiology / Q000628:therapy; D013926:Thrombopoietin / Q000627:therapeutic use
D001565:Benzoates; D016298:Hematopoietic Cell Growth Factors; D006834:Hydrazines; D007502:Iron Chelating Agents; D011720:Pyrazoles; D011961:Receptors, Fc; D011993:Recombinant Fusion Proteins; D013926:Thrombopoietin; D007501:Iron; C488777:romiplostim; D003676:Deferoxamine; C520809:eltrombopag