Inclusion Criteria

DISEASE CHARACTERISTICS: One of the following hematologic malignancies: Advanced
myelodysplastic syndromes Refractory anemia with excess blasts Refractory anemia with
excess blasts in transformation Chronic myelomonocytic leukemia Refractory acute myeloid
leukemia (AML) First salvage with primary refractory AML or first complete response (CR)
no greater than 12 months in duration or at least second salvage therapy Once maximum
tolerated dose is determined, intermediate AML prognosis (first CR duration greater than
12 months but less than 24 months) eligible Refractory acute lymphocytic leukemia
Refractory or transformed chronic lymphocytic leukemia Chronic myelogenous leukemia in
blastic phase No CNS disease

PATIENT CHARACTERISTICS: Age: Not specified Performance status: ECOG 0-2 Life expectancy:
Not specified Hematopoietic: No specified Hepatic: Bilirubin no greater than 2.0 mg/dL
SGOT or SGPT no greater than 2.0 times upper limit of normal Renal: Creatinine no greater
than 2.0 mg/dL Cardiovascular: No active congestive heart failure No uncontrolled angina
No myocardial infarction within the past 6 months Other: Not pregnant or nursing Fertile
patients must use effective contraception Negative pregnancy test No concurrent grade 4
infection No psychiatric disorder or mental disability No other life threatening illness

PRIOR CONCURRENT THERAPY: Biologic therapy: No concurrent biologic therapy Chemotherapy:
At least 30 days since prior cytotoxic therapy and recovered No concurrent chemotherapy
Endocrine therapy: Not specified Radiotherapy: No concurrent radiotherapy to greater than
25% of skeleton Surgery: No concurrent surgery Other: At least 3 weeks since prior
investigational drugs (including analgesics or antiemetics) Recovered from toxic effects
of any prior therapy