- Patients must not have received lenalidomide, azacitidine, vorinostat, or decitabine as treatment previously; any hematopoietic growth factors must be stopped for at least 14 days prior to registration; patients may have received low-dose cytarabine for MDS treatment previously, but they must have discontinued its use for at least 28 days prior to registration; patients may have received prior hydroxyurea per CMML treatment previously, but they must have discontinued its use for at least 7 days prior to registration; these patients will not be eligible if white blood cell (WBC) > 30,000/mm^3