A comparison was made between the therapeutic outcome of patients with diffuse large-cell non-Hodgkin's lymphoma treated with combination chemotherapy containing adriamycin (adriamycin regimen) and those treated with combination chemotherapy not containing adriamycin (non-adriamycin regimen). All the patients had no prior therapy, and there were no differences in any other background factors between the two treatment groups. Of 32 patients on the non-adriamycin regimen, 19 (59%) achieved complete response (CR) and 12 (38%) achieved partial response (PR). Of 20 patients on the adriamycin regimen, 14 (70%) achieved CR and 6 (30%) achieved PR. For those on the non-adriamycin regimen, the median duration of CR was 10 months, the projected 5-year relapse-free rate was 27%; the median survival time for all patients was 1 year 7 months; and the projected 5-year survival rate was 24%. For those on the adriamycin regimen, a median duration of CR was not reached, the projected 5-year relapse-free rate was 85%; the median survival time for all patients was 1 year 11 months; and the projected 5-year survival rate for all patients was 58%. These results show the superiority of combination chemotherapy containing adriamycin, indicating that adriamycin is a essential agent for the initial induction chemotherapy for the large-cell type of non-Hodgkin's lymphoma.