Twenty-nine patients with advanced non-Hodgkin's lymphoma (3 with follicular medium-sized cell type, 1 with follicular mixed cell type, 5 with diffuse small cell type, 17 with diffuse medium-sized cell type and 3 with lymphoblastic type) were treated with a four-drug combination chemotherapy consisting of adriamycin, vincristine, ifosfamide and prednisolone (AVIP). The objective response rate was 89% with a complete response rate of 55%. The median duration of complete response was 10 months ranging from 2 months to 6 years and 7 months. The median survival time calculated by the Kaplan-Meier method was 3 years and 9 months. As for the 17 patients with diffuse medium-sized cell type lymphoma, the complete response rate was 71%. Median survival time has not been reached, and 62% of the patients were alive after 5 years. Performance status, and presence or absence of systemic symptoms were important factors in predicting survival. The myelosuppressive toxicity of the regimen was well tolerated. No patients encountered life-threatening toxicity. This study demonstrated the efficacy of the AVIP regimen in patients with non-Hodgkin's lymphoma, and it appeared that patients with diffuse medium-sized cell type lymphoma were potentially curable.