58 NHL-patients (9 large cell centrocytic, 18 centroblastic, 16 immunoblastic, 15 lymphoblastic lymphomas) were treated immediately after diagnosis with CHOP-chemotherapy regardless of the extent of disease. Because of the advanced age of the majority of patients (median age 61 years, range 22-85 years) a reduced dose in the first two cycles was administered. Statistically significant prognostic variables influencing survival were the following: histologic subtypes according to the Kiel-classification (p less than 0,05), B-symptoms (p less than 0,001), blood sedimentation rate (p less than 0,02) and LDH (p less than 0,0005). With regard to prognosis there was no difference between patients over 60 years of age and younger ones (p less than 0,4). Patients achieving complete remission survived significantly longer (p less than 0,0001). Ann Arbor stages were of limited value, since patients with CS II disease and accumulation of risk factors (B-symptoms, abdominal disease, bulky tumor masses) showed a poorer outcome than patients with CS III who did not have these risk factors. A risk factor score summarizing features influencing prognosis is described and might be a useful tool in stratifying the heterogeneous group of NHL with unfavorable prognosis.