Phenylbutyrate and Tretinoin in Treating Patients With Hematologic Cancer

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed myelodysplastic syndrome (MDS) Refractory anemia Primary refractory leukopenia or thrombocytopenia with morphologic features of MDS Refractory anemia with excess blasts (RAEB) Refractory anemia with ringed sideroblasts RAEB in transformation Must have excess blasts or be hematopoietically compromised, defined as one of the following: RBC transfusion dependent Granulocyte count less than 1,000/mm^3 Platelet count less than 50,000/mm^3 OR Diagnosis of chronic myelomonocytic leukemia Hematopoietically compromised (as defined above) OR Excess blasts OR Evaluable disease related symptomatology (organomegaly or leukemia cutis) OR Diagnosis of acute myeloid leukemia WBC less than 20,000/mm^3 and stable for at least 2 weeks Unlikely to require cytotoxic therapy during study No CNS or pulmonary leukostasis or CNS leukemia PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Zubrod 0-2 Life expectancy: Not specified Hematopoietic: See Disease Characteristics Hemoglobin at least 8 g/dL (transfusion allowed) No disseminated intravascular coagulation Hepatic: Bilirubin less than 2.0 mg/dL (unless due to hemolysis or Gilbert's syndrome) Renal: Creatinine less than 2.0 mg/dL Other: Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception for 2 weeks prior, during, and for 3 months after study No active infection PRIOR CONCURRENT THERAPY: Biologic therapy: See Disease Characteristics At least 3 weeks since prior biologic therapy, including hematopoietic growth factors, and recovered Chemotherapy: See Disease Characteristics At least 3 weeks (1 month for MDS patients) since prior chemotherapy and recovered Endocrine therapy: Not specified Radiotherapy: At least 3 weeks since prior radiotherapy and recovered Surgery: Not specified