In two consecutive and unselected cohorts of diffuse large cell lymphoma (DLCL) patients with advanced stage disease (IIB or bulk or more) and aged < 60 years, we compared a standard (MACOP-B for 12 weeks, 60 patients) versus a high-dose chemotherapy programme (8 weeks of MACOP-B plus one or two cycles of intensification with mitoxanthrone, dexamethasone, high-dose Ara-C, and finally BEAM chemotherapy with autologous haemopoietic progenitor cell transplantation, 61 patients). 41 patients (68%) in the standard group and 51 (84%) in the high-dose chemotherapy group, achieved a complete remission (CR) or an uncertain complete remission (CRu) (P = 0.0491). With a median follow-up time of 28 months for the high-dose group and 63.5 months for the standard group, the actuarial estimate of event-free survival (EFS) at 2 years demonstrates a significant benefit (70% v 50%, P = 0.03) for patients treated with the intensive regimen. The analysis of subgroups of patients showed that only high-risk patients (two or three risk factors) benefitted from the high-dose chemotherapy programme. Nevertheless, the overall survival does not show a significant difference between the two treatment modalities. The treatment-related morbidity was similar and the mortality rate was 8% in the standard (MACOP-B) group and 3% in the high-dose chemotherapy programme. In conclusion, our results show that high-dose chemotherapy and autologous stem cell transplantation is a safe procedure which should be considered for the front-line treatment of non-Hodgkin lymphoma patients with poor prognostic features.