THE EFFECT OF IRON CHELATION ON HEMATOPOIESIS IN MDS PATIENTS WITH TRANSFUSIONAL IRON OVERLOAD

Long-term follow-up data are presented on changes in peripheral blood counts and Hb requirements of 11 patients with myelodysplastic syndrom es (MDS) during iron chelation treatment with desferrioxamine for up t o 60 months. The erythroid marrow activity was indirectly evaluated by repeated determinations of the serum transferrin receptor concentrati on. The efficacy of iron chelation was evaluated by repeated quantitat ive determination of the liver iron concentration by magnetic resonanc e imaging. Reduction in the Hb requirement (greater than or equal to 5 0%) was seen in 7/11 (64%) patients. Five patients (46%) became blood transfusion independent. Platelet counts increased in 7/11 (64%) patie nts and the neutrophil counts in 7/9 (78%) evaluable patients. All pat ients in whom iron chelation was highly effective showed improvement o f erythropoietic output accompanied by an increase in the serum transf errin receptor concentration. It is concluded that reduction in cytope nia in MDS patients may be accomplished by treatment: with desferrioxa mine, if the iron chelation is efficient and the patients are treated for a sufficiently long period of time, Exactly how treatment with des ferrioxamine works remains a challenge for further investigation.