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the patient ( female ) was diagnosed in march 2002 at the age of 61 with primary myelofibrosis ( pmf ) according to the world health organization diagnostic criteria ( 1 ) .
( lille system ) ( 2 ) , which is associated with a median survival of 26 months . from the time of diagnosis the patient 's hemoglobin was 57 g / dl , necessitating packed red blood cell ( prbc ) transfusions .
the mean cellular volume was 78 fl and blood smear showed red cell poikilocytosis with dacryocytes .
there was mild thrombocytopenia ( platelets 90  10/l ) and a normal white blood cell count ; bcr / abl was negative .
bone marrow biopsy showed 20% cellularity with advanced stage of fibrosis , mf-2 according to thiele et al .
the patient required approximately 23 prbc units per month ( total of 29 units ) to maintain a pretransfusional hemoglobin level of 8.5 g / dl . in june 2003 ,
the patient entered a phase ii trial evaluating the efficacy and safety of once - daily oral chelator deferasirox in adults and children with a range of transfusion - dependent anemias .
baseline assessment of this patient ( table 1 ) showed that bone marrow cellularity had decreased to 10% with no modification in fibrosis score .
patient 's characteristics before chelation and after 1 yr of chelation therapy lic , liver iron concentration . with dosing based on liver iron concentration , deferasirox was administered at 20 mg / kg / d for the duration of the 1-yr study .
after 2 months of deferasirox therapy the patient 's transfusion requirement progressively decreased ( 10 prbc units were administered during the initial chelation therapy period ) and transfusion therapy was ceased 5 months after study entry due to stable hemoglobin levels of 11.412.4 g / dl . at study end ,
re - evaluation of myelofibrosis by routine hematological evaluation and bone marrow biopsy revealed increased hemoglobin levels ( 12.5 g / dl ) , decreased cd34-positive cell counts , a negative direct coombs test , a reduction in teardrop cells , and normalization of mean corpuscular volume ( 90 fl ) .
even if chelation therapy was not directly targeted to pmf a clinical improvement was obtained according to the international working group for myelofibrosis research and treatment response criteria ( 4 ) . due to the reduction in transfusions ,
chelation therapy was finally interrupted in january 2005 when the patient 's body iron content was within an acceptable range ( serum ferritin 953 g / l and transferrin saturation 42% ) . to date ( january 2007 ) , the patient remains transfusion free ( serum ferritin 499 g / l and transferrin saturation 34% ) , with a hemoglobin level of approximately 11 g / dl and normal hematological parameters ( platelet count 120  10/l ) .
primary myelofibrosis is an uncommon but severe condition associated with poor prognosis . for the majority of patients ,
therapy is palliative and many become transfusion dependent . transfusion requirement often increases during the course of the disease due to collagen deposition in the bone marrow and progressive impairment of erythropoiesis .
the patient described here received iron chelation therapy as part of the clinical evaluation of oral deferasirox and experienced not only the anticipated fall in iron levels , but also an unexpected improvement in erythropoiesis .
this improvement was so marked that the transfusion requirement decreased progressively and was ultimately deemed unnecessary , an effect that continued after cessation of chelation therapy
. clinical improvement ( 4 ) was evident as the patient became transfusion free , leading to a dramatic improvement in quality of life .
this has been sustained to date ( 3 yr after cessation of transfusion requirement and more than 22 months after stopping chelation ) .
although iron chelation therapy has not been widely evaluated in patients with acquired anemia , reports have shown an improvement in bone marrow function in patients with myelodysplastic syndromes receiving deferoxamine ( 5 ) and in a patient with pmf receiving deferiprone ( 6 ) .
a variety of mechanisms are possible in different diseases ( 7 ) , those postulated include : a limited cytoreductive effect ( 5 ) , iron redistribution to the hemopoietic tissue ( 8) , ferrokinetic changes ( 9 ) , suppression of increased apoptosis , and mitochondrial damage secondary to intracellular iron deposition ( as it has been demonstrated that iron chelators can pass the erythroblast membrane ) ( 10 ) . because of the persistent effect after chelation withdrawal , the latter appears to be the most promising mechanism to be investigated .
of course , a stochastic effect can not be excluded , particularly in pmf in which a 
bizarre behavior has been described ( 7 ) , but the increasing number of similar reports in the literature support the need for a controlled clinical trial in transfusion - dependent acquired hemopoietic stem cell disorders to investigate the potential benefit of chelation on erythropoiesis .
transfusional iron overload in patients with chronic anemias can result in multiple organ failure . 
 experience in the management of iron overload in patients with myelodysplastic syndromes is limited , as many do not receive chelation therapy due to short - life expectancy and the difficulties associated with the administration of the current reference standard chelator , deferoxamine . 
 there have , however , been some reports of reduced transfusion requirement associated with chelation therapy in patients with myelodysplastic syndromes and myelofibrosis . here , we discuss a patient with primary myelofibrosis and related transfusion - dependent anemia who received chelation therapy with the once - daily oral iron chelator , deferasirox . 
 in addition to the reduced iron levels , the patient demonstrated an unexpected reduction in blood transfusion requirement , ultimately resulting in long - lasting transfusion - free survival .