Observation in Patients With Diffuse Large B-Cell Non-Hodgkin's Lymphoma Treated on Clinical Trial CAN-NCIC-LY9

OBJECTIVES: * Gain information on the long-term efficacy of 6 courses of CHOP (cyclophosphamide, doxorubicin hydrochloride, prednisone, and vincristine)-like chemotherapy with vs without rituximab (plus involved-field radiotherapy to primary bulky disease) in young patients with good-prognosis diffuse large B-cell non-Hodgkin's lymphoma treated on protocol CAN-NCIC-LY9. * Gain information on late toxicities, including secondary neoplasm occurring in young good-prognosis patients treated on protocol CAN-NCIC-LY9. OUTLINE: This is a multicenter study. Patients successfully completing treatment on protocol CAN-NCIC-LY9 are followed every 3 months for 2 years, every 6 months for 3 years, and then annually thereafter. PROJECTED ACCRUAL: A total of 667 patients will be accrued for this study.