If you respond to the third cycle of bortezomib/rituximab, you will have some of your stems cells collected. After the stem cell collection, 1 cycle of cladribine, cyclophosphamide, and rituximab will be given. Cladribine will be given through a vein once a day over 2 hours on Days 1-5. Cyclophosphamide is taken by mouth, twice a day on Days 1-5, and rituximab is given through a vein once a week for 4 weeks.