FCR or BR in Patients With Previously Untreated B-Cell Chronic Lymphocytic Leukemia

RATIONALE: Drugs used in chemotherapy, such as fludarabine, cyclophosphamide, and bendamustine, 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 block the ability of cancer cells to grow and spread. Others find cancer cells and help kill them or carry cancer-killing substances to them. It is not yet known whether giving fludarabine and cyclophosphamide together with rituximab is more effective than giving bendamustine together with rituximab in treating chronic lymphocytic leukemia. PURPOSE: This randomized phase III trial is studying fludarabine, cyclophosphamide, and rituximab to see how well they work compared with bendamustine and rituximab in treating patients with previously untreated B-cell chronic lymphocytic leukemia.