Combination Chemotherapy Followed By Peripheral Stem Cell Transplantation or Isotretinoin in Treating Patients With Acute Myeloid Leukemia, Myelodysplastic Syndrome, or Acute Lymphocytic Leukemia

DISEASE CHARACTERISTICS: Histologically proven poor prognosis acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), or recurrent/refractory acute lymphocytic leukemia, including: Myelodysplastic syndrome (MDS) stages B and C Refractory anemia, refractory anemia with ringed sideroblasts, or refractory anemia with excess blasts (between 5% and 20% myeloblasts) MDS with increased erythroblasts or monocytoblasts of no greater than 20% MDS in transformation (between 20% to 30% myeloblasts) or acute nonlymphoblastic leukemia (at least 30% myeloblasts) Chronic myelomonocytic leukemia Poor prognosis refractory or recurrent acute myeloid leukemia after complete response Secondary or therapy related AML or MDS AML blastic crisis of chronic myelogenous leukemia or other myeloproliferative disorders such as polycythemia vera, essential thrombocytopenia, or agnogenic myeloid metaplasia PATIENT CHARACTERISTICS: Age: 19 to 90 Performance status: ECOG 0-2 Life expectancy: Not specified Hematopoietic: Not specified Hepatic: Bilirubin no greater than 2.0 mg/dL SGOT or SGPT less than 2.0 times upper limit of normal Renal: Normal serum creatinine Cardiovascular: No congestive heart failure No symptomatic ischemic heart disease Other: Not pregnant or nursing Fertile patients must use effective contraception HIV negative No uncontrolled infection No poorly controlled diseases (e.g., diabetes, systemic lupus erythematosus) No history of psychiatric disorders No other malignancies within the past 5 years except adequately treated basal or squamous cell skin cancer or carcinoma in situ of the cervix No concurrent severe medical problems No history of allergic reaction to topotecan and its derivatives PRIOR CONCURRENT THERAPY: Biologic therapy: No other concurrent immunotherapy Chemotherapy: No prior topotecan At least 4 weeks since prior chemotherapy No other concurrent chemotherapy Endocrine therapy: Not specified Radiotherapy: No concurrent radiotherapy Surgery: Not specified Other: No other investigational drugs within 30 days of study No other concurrent investigational therapy except for basal cell skin cancer