Secondary myelodysplasia usually has a poorer prognosis than does de novo myelodysplasia. Prognosis is directly related to the number of bone marrow blast cells and to the degree of peripheral blood cytopenias.
Prognosis is also related to the type of myelodysplastic syndrome.
Treatment consists largely of supportive care. Judicious use of platelet and blood transfusions may prevent or delay alloimmunization and iron overload, and favorably affect prognosis. The MDS are characterized by abnormal bone marrow and blood cell morphology. Megaloblastic erythroid hyperplasia with macrocytic anemia associated with normal B12 and folate levels is frequently observed. Circulating granulocytes are frequently severely reduced in number, often hypogranular, and display the acquired pseudo Pelger-Huet abnormality.