Decitabine and Valproic Acid in Treating Patients With Refractory or Relapsed Acute Myeloid Leukemia or Previously Treated Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma

Inclusion Criteria: * Patients with AML (Stratum I) or CLL/SLL (Stratum II) will be enrolled * Patients in stratum I will have one of the following: * Primary refractory or relapsed (in 1 year or less) disease and not a candidate for potentially curative therapy * Untreated AML patients who are not candidates for chemotherapy * Patients in stratum I must have a normal WBC (=\< 10 x 10\^9/L) or a WBC =\< 40 x 10\^9/L that is stable for 1 week (this may be sustained with hydroxyurea prior to starting therapy and during the first 4 days of therapy if clinically indicated) * Patients in stratum II will have received at least one prior therapy for CLL/SLL that has included a purine analog; patients in stratum II with a history of severe autoimmune disease or requiring therapy with chronic corticosteroids or who have any other specific relative contraindications to receive a purine analog and, therefore, have received another form of therapy that include alkylating agents will be eligible to participate * Performance status - ECOG 0-2 * At least 12 weeks life expectancy * Stratum II: * No uncontrolled autoimmune hemolytic anemia * No idiopathic thrombocytopenia purpura * Bilirubin =\< 1.5 mg/dL * ALT and AST =\< 2 times upper limit of normal * Creatinine =\< 2.0 mg/dL * No active infection requiring IV antibiotics * HIV negative * No other severe medical condition that would preclude study participation * No psychiatric condition that would preclude study compliance * …