<qa>  What is the name of the treatment that patients receive?- Immunochemotherapy and radiotherapy: Patients receive CHOP chemotherapy comprising cyclophosphamide IV over 15 minutes, doxorubicin hydrochloride IV, and vincristine IV on day 1 and oral prednisone once daily on days 1-5. Patients also receive pegfilgrastim subcutaneously on days 4, 18, 32, 46, 60, and 74. Treatment with CHOP chemotherapy repeats every 14 days for up to 6 courses in the absence of disease progression or unacceptable toxicity. Patients who show no response after course 4 of CHOP chemotherapy proceed to salvage chemotherapy off study. 