Phase II Research Study of Arsenic Trioxide (Trisenox) in Patients With Myelodysplastic Syndrome (MDS)

Inclusion Criteria: * Diagnosis of Myelodysplastic Syndrome by FAB. Can be made with cytogenetic analysis of Bone Marrow or Hematologist evaluation * Patient must have had bone marrow biopsy and aspiration to confirm diagnosis within 60 days prior to treatment * ECOG performance status of 0-2 * An EKG must be performed within 7 days prior to treatment to confirm QT interval \<460msec. * Serum creatinine less than or equal to 2.5 times the upper limit of normal. * Serum bilirubin less than or equal to 2.5 times the upper limit of normal. * Serum potassium greater than or equal to 4.0 mEq/dL and serum magnesium greater than or equal to 1.8 mg/dL. If these serum electrolytes are below the specified limits on the baseline laboratory tests, electrolytes should be administered to bring the serum concentrations to these levels before administering arsenic trioxide. * Patients must be 18 years of age to participate in this study Exclusion Criteria: * Pregnant or nursing women, and men or women of childbearing potential who are unwilling to employ adequate contraception. * Corrected QT interval of greater than or equal to 460msec in the presence of serum potassium and magnesium values within normal range. * Significant CHF, coronary is ischemia or serious Arrhythmias including conduction delays. * Peripheral neuropathy greater than or equal to 2. * Evidence of active infection * Concurrent treatment with maintenance therapy, cytotoxic chemotherapy, radiation, or investigational agents. * Inability or unwillingness to comply with the treatment protocol, follow up, or research tests.