The results of CHOP treatment in 63 patients with intermediate and high-grade non-Hodgkin's lymphoma (Working Formulation D to I), Ann Arbor stage I to IV were analyzed. The response rate was 87% 71% complete remission and 16% partial remission with a mean duration of 22 months. The 5-year actuarial survival was 61% (95% confidence interval, 51-70% The treatment was well tolerated and no deaths due to acute toxicity were observed. Poor prognostic factors in univariate analysis were: high-grade histology, stages III and IV, B symptoms, ≥ 4 affected lymph node regions, Karnofsky index ≤70, erythrocyte sedimentation rate (ESR) <60mm, haemoglobin >100g/1 and elevated lactic dehydrogenase (LDH). Poor prognostic factors in multivariate analysis were: high-grade histology, stages III and IV, haemoglobin > 100 g/1 and elevated LDH. In summary, good results were obtained with CHOP chemotherapy, without severe toxicity. ©1994 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.