<qa>  What is the diameter of a patient?Patients are evaluated 2-4 weeks after completion of CHOP. Patients with initial bulky disease i.e., diameter 7.5 cm or extranodal involvement AND achieving complete remission CR, unconfirmed CR CRu, or partial remission undergo radiotherapy 5 days a week for 4 weeks. Patients who do not achieve CR or CRu 2 months after completion of radiotherapy proceed to salvage chemotherapy off study. 