Bortezomib and Rituximab in Treating Patients With Non-Hodgkin's Lymphoma

"Arm I: Patients receive bortezomib IV over 3-5 seconds on days 1, 4, 8, and 11. Patients also receive rituximab IV on days 1, 8, and 15 of course 1 only and on day 1 of course 2 only. Treatment with repeats every 21 days for up to 5 courses in the absence of disease progression or unacceptable toxicity.~* Arm II: Patients receive bortezomib IV over 3-5 seconds on days 1, 8, 15 and 22. Patients also receive rituximab IV on days 1, 8, 15, and 22 of course 1 only. Treatment repeats every 35 days for up to 3 courses in the absence of disease progression or unacceptable toxicity.~Patients in either arm may crossover to the other arm if treatment is found to be ineffective."