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