Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically diagnosed refractory anemia, refractory anemia
with excess blasts, refractory anemia with excess blasts in transformation, refractory
anemia with ringed sideroblasts, or chronic myelomonocytic leukemia with significant
cytopenias of at least 4 weeks duration No more than 1 prior treatment for disease Not
eligible for allogeneic bone marrow transplantation if less than 60 years of age

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Zubrod 0-2 Life expectancy:
At least 12 weeks Hematopoietic: Hematocrit less than 26% (or requiring transfusion) for
at least 4 weeks Absolute neutrophil count less than 1000/mm3 for at least 4 weeks
Platelet count less than 50/mm3 for at least 4 weeks Hepatic: Bilirubin less than 1.5
mg/dL Transaminase less than 2.5 times upper limit of normal Renal: Creatinine less than
1.5 mg/dL Creatinine clearance of at least 60 mL/min Other: Not pregnant or lactating
Fertile patients must use effective contraception while on study and for 100 days
afterwards No uncontrolled or life-threatening infection

PRIOR CONCURRENT THERAPY: Biologic therapy: No concurrent immunotherapy No concurrent
treatment with growth factors Chemotherapy: At least 4 weeks since prior chemotherapy (8
weeks for mitomycin or nitrosourea) and recovered Endocrine therapy: No concurrent use of
steroids Radiotherapy: At least 4 weeks since prior radiation therapy and recovered
Surgery: Not specified