64 patients with extensive non-Hodgkin lymphomas were treated with a modified MOPP scheme. 41 patients had stage IV disease. 59 patients responded to treatment. In 22 cases complete remission was obtained and in 37 cases partial remission. The proportion of complete remissions was the same for reticulosarcoma (9 out of 28) and lymphosarcoma (7 out of 22). The remission rate for Brill-Symmers disease was higher (6 out of 14). For patients with lymphosarcoma the average duration of complete remission was 26.9 months and for patients with reticulosarcoma 25 months. 42 of the 59 patients who responded to treatment survived one year, 33 of them two or more years. After a two-year period there were no more deaths.