OBJECTIVES: I. Estimate complete or partial remission, hematologic improvement, and cytogenic response rate when oral topotecan is given twice a day for 5 days versus once a day for 10 days to patients with myelodysplastic syndromes. II. Evaluate the safety and toxicity of oral topotecan in these patients. III. Evaluate whether there are morphologic and/or cytogenetic subsets of the myelodysplastic syndromes that will respond optimally to this regimen. IV. Evaluate the change in the percentage of bone marrow blast cells in these patients during treatment. V. Evaluate the time to transformation to acute myeloid leukemia (AML) or death in this patient population.