5-azacitidine: An alternative treatment of myelodysplastic syndromes in patient with refractory response to hematopoietic growth factor, a case report and review of literatures.

Myelodysplastic Syndrome (MDS) comprises a heterogeneous group of clonal hemopathies derived from an abnormality affecting a multipotent hematopoietic stem cell and characterized by maturation defects resulting in ineffective hematopoiesis. It most frequently occurs in elderly patients. Despite trials testing numerous agents in patients with MDS, no single drug has yet emerged as the accepted standard of treatment. Most MDS patients, due to their age and co morbidity, are not eligible for allogeneic hematopoietic stem cell transplantation; the only established curative regimen. The effect of available lineage-specific growth factors is limited to improvement of single lineages and has not resulting in the survival benefit. Treatment with low dose Ara-C is disappointing in regard to response rate or duration. No benefit has been demonstrated in differentiation inducers such as retinoids and Vitamin D3 as single agents. We report a case of a patient with transfusion dependent MDS who was not a candidate for allogeneic stem cell transplantation or cytotoxic chemotherapy. who also failed to response to erythropoietin support but had a favorable response to 5-azacitidine. His blood transfusion requirement reduced significantly, and was correlated with the remarkable improvement of the pancytopenia, particularly anemia and thrombocytopenia after receiving the investigational therapy with 5-azacitidine. In summary, 5-azacitidine appears to be a promising alternative therapy for patient with refractory anemia secondary to MDS.