DISEASE CHARACTERISTICS: Diagnostically proven intermediate, advanced, or high risk chronic lymphocytic leukemia of the B cells with marrow tumor reduced by prior therapy Marrow tumor content no greater than 30% of total nucleated cells Patients age 50 and under who have high risk disease are eligible Patients age 65 and under who have intermediate or high risk disease that has failed at least 1 therapy including an alkylating agent or fludarabine are eligible No history of transformation to aggressive lymphoma (Richter's syndrome)