Non-Hodgkin's lymphoma (NHL) is a malignancy that occurs frequently in the elderly with a median age greater than 60 years. However, most chemotherapy trials have included predominantly patients less than 60 years of age. We treated 157 patients with diffuse aggressive NHL between September 1982 and May 1986 with cyclophosphamide, Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), procarbazine, bleomycin, vincristine, and prednisone (CAP/BOP). There were no treatment exclusions for age. Patients in this study ranged in age from 15 to 91 years (median, 63) with 112 patients greater than or equal to 60 years of age. The overall complete remission (CR) rate was 65% with no significant difference for age less than 60 (76%) v age greater than or equal to 60 (61%) (P = .18). With a median 36-month follow-up (range, 22 to 65 months), the overall 5-year survival was 42%. The patients less than 60 years old had a 62% 5-year survival in contrast to a 34% 5-year survival in those patients greater than or equal to age 60 (P = .01). The deaths attributed to tumor or treatment-related toxicity were similar above and below age 60. The difference in survival was due to other causes of death not obviously related to the lymphoma or its therapy-occurring in 22% of patients greater than or equal to 60 years of age but only 2% of patients less than 60 years (P = .005). Our data supports the position that aggressive NHL in elderly patients is not significantly less responsive than in younger patients; however, the inclusion of older patients in clinical trials will decrease the overall survival secondary to deaths due to apparently unrelated causes.