Decitabine in Treating Patients With Myelofibrosis

Inclusion Criteria: * Patients must have histologically or cytologically confirmed myeloid metaplasia with myelofibrosis (this includes all subtypes - chronic idiopathic myelofibrosis or angiogenic myeloid metaplasia, post thrombocythemic and post polycythemic myelofibrosis); patients must have anemia (hemoglobin \< 11 g/dL) or palpable splenomegaly (measured in cm from costal margin - to be eligible); patients with palpable splenomegaly must have spleen size documented ultrasonographically as well; they must also meet standard diagnostic criteria for MMM * Patients with morphologic evidence of advanced phases of the disease including accelerated (10-19% blasts) phase or with evidence of evolution to acute leukemia (\>= 20% blasts) are also eligible for this study * The Italian Diagnostic Criteria for MMM * Necessary criteria * Diffuse bone marrow fibrosis * Absence of the Philadelphia chromosome or BCR-ABL rearrangement in peripheral blood cells * Optional criteria * Splenomegaly of any grade * Anisopoikilocytosis with tear drop erythrocytes * Presence of circulating immature myeloid cells * Presence of circulating erythroblasts * Presence of clusters of megakaryoblasts and anomalous megakaryocytes in bone marrow sections * Myeloid metaplasia * Diagnosis of MMM is acceptable if the following combinations are present * The two necessary criteria plus any other two optional criteria when splenomegaly is present OR * The two ne…