DISEASE CHARACTERISTICS: Diagnosis of chronic phase chronic myelogenous leukemia (CML) Philadelphia (Ph) chromosome positive OR Bcr/Abl positive Refractory to or intolerant of interferon alfa therapy Failure to achieve complete response for at least 1 month after at least 6 months of interferon alfa therapy OR At least 65% Ph chromosome positivity in bone marrow after at least 1 year of interferon alfa therapy OR At least 30% increase in Ph chromosome positive bone marrow cells in samples taken at least 1 month apart or increase to at least 65% while receiving interferon alfa therapy OR At least 100% increase in WBC count to at least 20,000/mm3 in samples taken at least 2 weeks apart while receiving interferon alfa therapy OR At least grade 3 nonhematologic toxicity persisting for more than 2 weeks while receiving interferon alfa therapy (must be more than 3 months from time of diagnosis) No greater than 15% blasts or basophils in peripheral blood or bone marrow Less than 30% blasts plus promyelocytes in peripheral blood or bone marrow