Patients with lymphosarcoma and reticulum cell sarcoma were randomly allocated to treatment with cyclophosphamide alone or to two dosage levels of combinations of cyclophosphamide, vincristine and prednisone. Remission induction was significantly better for the combinations with lymphosarcoma patients and for the high dose combination with reticulum cell sarcoma patients. Toxicity, more pronounced with high combination, was tolerable. Remissions as measured by decrease in tumor size were associated with improvement in hemoglobin, performance, food intake, weight and fever. The study provides impetus for further trial with other drug combinations and schedules.