The trial included 85 previously untreated patients (median age 61 years) with stage III or IV non-Hodgkin's lymphoma (NHL) of the subtypes centrocytic lymphoma, diffuse centroblastic lymphoma, immunocytoma, immunoblastic lymphoma, or unclassified lymphoma of high grade malignancy. The patients were randomized to 9 monthly treatment cycles of CHOP (cyclophos-phamide, doxorubicin, vincristine, prednisone) or CisEBP (cis-platin, bleomycin, etoposide, prednisone). Patients who had failed to achieve even a partial response (PR) after the completion of 2 cycles were switched to the alternative regimen. Complete response (CR) on primary treatment was obtained in 70% (55–83%) of CHOP-treated patients and in 25% (13–41%) of CisEBP-treated patients (p = 0.0004). Secondary CHOP treatment produced CR in 7 (30%) of 24 patients and secondary CisEBP treatment led to CR in 2 (15%) of 14 patients. The median survival was 3.4 years in the CHOP arm and 2.6 years in the CisEBP arm (p = 0.78). Hematologic toxicity was mainly leukocy-topenia and anemia in both treatment arms. Non-hematological toxicity was slight, and late toxicity was insignificant. Three treatment-related deaths were noted. We conclude that CHOP induces more remissions than CisEBP in advanced lymphomas of high grade malignancy.