Combination Chemotherapy Plus PSC-833 in Treating Children With Refractory or Relapsed Acute Leukemia

DISEASE CHARACTERISTICS:

   - Acute myeloid leukemia (AML) in one of the following categories:

   - First relapse if initial CR less than 6 months

   - Refractory to first or second induction with daunomycin, cytarabine, and thioguanine
   (DAT) or other anthracycline-containing regimens

   - Relapse following bone marrow transplantation provided good trilineage engraftment
   followed transplant and greater than 6 months since transplant

   - Presentation with secondary AML or AML evolving from myelodysplastic syndrome --Acute
   lymphocytic leukemia in one of the following categories:

   - In second or subsequent relapse or failed second or later induction attempts
   regardless of prior remissions

   - Relapsed following bone marrow transplantation provided good trilineage engraftment
   followed transplant and greater than 6 months since transplant

   - No isolated CNS or extramedullary relapse

PATIENT CHARACTERISTICS:

   - Age: Under 22 at diagnosis

   - Performance status: Karnofsky 50-100% (ECOG 0-2)

   - Lansky 40-100% (in patients under 12 years of age)

   - Life expectancy: At least 8 weeks

   - Bilirubin less than 1.5 mg/dL

   - ALT less than twice normal

   - Creatinine normal for age (within 2 standard deviations) OR glomular filtration rate
   at least 70 mL/min

   - Albumin at least 3 g/dL

   - Ejection fraction greater than 50% at rest or with 5% increase with exercise OR
   shortening fraction greater than 27% by echocardiogram

   - No history of clinical heart failure

   - No uncontrolled infection

   - No anticonvulsant therapy

   - No history of allergic reactions or anaphylaxis to etoposide not remediable by
   premedication

   - Not pregnant or nursing

   - Fertile patients must use effective contraception

   - Third percentile weight for height

PRIOR CONCURRENT THERAPY:

   - At least 4 weeks since chemotherapy and recovered

   - Prior cumulative anthracycline dose no greater than 360 mg per square meter

   - Hydroxyurea therapy allowed just prior to study for rapidly rising blast count