Fludarabine, Cyclophosphamide, and Rituximab in Treating Patients With Prolymphocytic Leukemia

RATIONALE: Drugs used in chemotherapy, such as fludarabine and cyclophosphamide, work in different ways to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Monoclonal antibodies, such as rituximab, can block cancer growth in different ways. Some find cancer cells and kill them or carry cancer-killing substances to them. Others interfere with the ability of cancer cells to grow and spread. Giving fludarabine and cyclophosphamide together with rituximab may kill more cancer cells. PURPOSE: This phase II trial is studying how well giving fludarabine and cyclophosphamide together with rituximab works in treating patients with B-cell prolymphocytic leukemia.