One hundred twenty-six patients with diffuse large-cell lymphoma were treated with methotrexate with leucovorin, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B) between April 1981 and June 1986. Univariate and multivariate analyses were performed using overall survival as of September 1989 as the end point. Four independent negative predictors of survival were identified: presence of B symptoms; more than two involved lymph node sites; more than one extranodal site (variables related to tumor burden), and age older than 60, a variable related to the patient's ability to tolerate treatment. Each variable contributed the same relative risk of dying and, accordingly, this simple predictive formula was developed empirically: (4-N) x 30 = the approximate percentage of chance of survival at 5 years. "N" is the number of predictive variables present. The same four predictors were also found to be significant by multivariate analysis when only those patients achieving a complete response were analyzed.