Inclusion Criteria

DISEASE CHARACTERISTICS:

- One of the following diagnoses:

- Primary refractory acute myeloid leukemia (AML)

- More than 10% blasts in the bone marrow or blood after recovery from 2
courses of standard cytarabine- and anthracycline-based induction
chemotherapy

- No prior remission

- Relapsed AML

- More than 10% blasts in the bone marrow or blood after documented remission

- Prior remission lasted more than 30 days

- No prior treatment for current relapse

- CD33 expression on at least 20% of leukemia blast cells at initial diagnosis for
primary refractory patients or at the time of relapse for all other patients

- No active CNS involvement

PATIENT CHARACTERISTICS:

Age:

- 17 and over

Performance status:

- 0-2

Life expectancy:

- Not specified

Hematopoietic:

- See Disease Characteristics

- WBC less than 30,000/mm^3

Hepatic:

- Bilirubin less than 2.0 mg/dL

- No veno-occlusive disease of the liver

- No chronic liver disease unless due to AML

Renal:

- Not specified

Other:

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No active serious infection

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- At least 6 months since prior stem cell transplantation

Chemotherapy:

- See Disease Characteristics

- Prior etoposide and/or thioguanine during remission induction allowed

- Prior hydroxyurea for control of AML allowed

- At least 24 hours since prior hydroxyurea

- At least 3 months since prior high-dose cytarabine (greater than 2
g/m^2/dose)-containing regimen

- No other concurrent chemotherapy

Endocrine therapy:

- Concurrent steroids for adrenal failure, hypersensitivity reactions, or septic shock
allowed

- Concurrent ophthalmic corticosteroids allowed

- Concurrent hormones for nondisease-related conditions (e.g., insulin for diabetes or
estrogens or progestins for gynecologic conditions) allowed

Radiotherapy:

- No concurrent radiotherapy

Surgery:

- Not specified

Other:

- More than 2 months since prior cytotoxic therapy