PRIOR CONCURRENT THERAPY: Biologic therapy: See Disease Characteristics No concurrent growth factors Chemotherapy: See Disease Characteristics Recovered from prior chemotherapy Prior hydroxyurea or low-dose cytarabine (less than 100 mg subcutaneously) to lower blast counts allowed if discontinued on day 1 of study therapy No concurrent antineoplastic chemotherapy Endocrine therapy: Concurrent corticosteroids allowed, including antiemetics Radiotherapy: Recovered from prior radiotherapy No concurrent radiotherapy Surgery: Not specified