 - Chemoimmunotherapy R-CHOP or R-CVP: Patients receive R-CHOP comprising rituximab IV, cyclophosphamide IV, doxorubicin hydrochloride IV, and vincristine IV on day 1 and oral prednisolone on days 1-5. Alternatively, patients who have already been exposed to prior tolerance doses of anthracyclines receive R-CVP comprising rituximab IV, cyclophosphamide IV, and vincristine IV on day 1 and oral prednisolone on days 1-5. Treatment repeats every 3 weeks for up to 3 courses. 