Inclusion Criteria

DISEASE CHARACTERISTICS:

- Relapsed or refractory acute myelogenous leukemia OR

- Elderly patients with newly diagnosed acute myelogenous leukemia not eligible for
standard therapy OR

- "High-risk" myelodysplastic syndrome, including:

- Refractory anemia with excess blasts

- Refractory anemia with excess blasts in transformation

- Chronic myelomonocytic leukemia OR

- Relapsed or refractory chronic lymphocytic leukemia

- Not eligible for transplant protocols at MSKCC or refuses transplant

- Not eligible for a higher priority protocol (e.g., bone marrow transplantation)

PATIENT CHARACTERISTICS:

Age:

- Over 18

Performance status:

- Not specified

Life expectancy:

- Not specified

Hematopoietic:

- Platelet count at least 25,000/mm^3

Hepatic:

- Bilirubin no greater than 2.0 mg/dL

- Transaminase levels less than 3 times upper limit of normal

- PT no greater than 14 seconds

- PTT no greater than 34.6 seconds

Renal:

- Creatinine no greater than 2.0 mg/dL OR

- Creatinine clearance greater than 60 mL/min

Other:

- Not pregnant or nursing

- No history of abnormal bleeding or unexplained bleeding disorders

- No history of peptic ulcer disease

- No salicylate allergy

- No other concurrent active malignancy

- No other concurrent illness that would preclude study assessment to a significant
degree

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- See Disease Characteristics

Chemotherapy:

- Not specified

Endocrine therapy:

- Not specified

Radiotherapy:

- Not specified

Surgery:

- Not specified