RATIONALE: Monoclonal antibodies, such as epratuzumab, 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. Drugs used in chemotherapy, such as cytarabine and clofarabine, work in different ways to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Giving epratuzumab together with cytarabine and clofarabine may kill more cancer cells.