One-hundred patients affected with non-metastatic osteosarcoma of the limbs were treated according to a new adjuvant chemotherapy protocol. Preoperative treatment consisted in high doses of methotrexate (i.v.), followed after one week by cisplatin continuous intra-arterial infusion for 72 hours and adriamycin in intravenous infusion for 8 hours. There was good clinical and radiographic response in all of the cases, and conservative treatment was used in 86 cases (86%). A postsurgery histological examination of the segment showed "good" necrosis (greater than 90%) in 75 patients (75%). The incidence of "good" necroses obtained with this protocol was significantly higher as compared to that observed previously at our Center when a preoperative chemotherapy scheme was used, which involved methotrexate and cisplatin alone. Up until now, patients with a good histological response to preoperative chemotherapy have always had an excellent prognosis. Thus, it is our belief that the 23% increase in good histological responses observed must correspond to an increase in the percentage of healing. The preliminary results (83% of patients with no signs of disease) seem to encourage our hypothesis.