- Arm IV (R-CHOP-14 and radiotherapy): Patients receive R-CHOP as in arm I. Patients also receive G-CSF an in arm III. Treatment repeats every 14 days for up to 6 courses in the absence of disease progression or unacceptable toxicity. Beginning 2-6 weeks after the last course of R-CHOP, patients who achieve CR undergo radiotherapy as in arm II.