Combination Chemotherapy in Treating Patients With Recurrent or Refractory Leukemia

DISEASE CHARACTERISTICS: Acute myelogenous leukemia (M0-M7) and acute lymphoblastic leukemia (L1-L2) Refractory or in first or subsequent relapse Circulating blasts present OR Greater than 5% blasts in bone marrow Acute myelogenous leukemia secondary to myelodysplastic syndrome or cytotoxic therapy Untreated OR Maximum of 2 intensive induction regimens Chronic myelogenous leukemia in blastic or lymphoid crisis Untreated OR Maximum of 2 intensive induction regimens No CNS leukemia PATIENT CHARACTERISTICS: Age: Over 18 Performance status: ECOG 0-3 Life expectancy: At least 4 weeks Hematopoietic: Not specified Hepatic: Bilirubin no greater than 2.0 mg/dL AST and ALT less than 3 times normal Alkaline phosphatase less than 3 times normal Renal: Creatinine no greater than 1.5 mg/dL OR Creatinine clearance greater than 60 mL/min Cardiovascular: No myocardial infarction within 6 months No active ischemic cardiac disease No poorly controlled congestive heart failure No other symptomatic cardiac disease Left ventricular ejection fraction at least 40% Pulmonary: No symptomatic restrictive or obstructive lung disease Other: No severe neurologic disease No active infection unless stable on antimicrobial therapy or fever is tumor related HIV negative Not pregnant or nursing Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: At least 2 weeks since prior cytotoxic therapy (except hydroxyurea and steroids) Biologic therapy: No prior bone marrow transplantation At least 3 days since prior hematopoietic growth factors Chemotherapy: No prior topotecan or camptothecin analogues Prior etoposide allowed Endocrine therapy: Not specified Radiotherapy: Not specified Surgery: Not specified