Two hundred forty-three patients who had pathologically verified primary osteosarcomas of bone, treated at The University of Texas System Cancer Center, M. D. Anderson Hospital and Tumor Institute over a 24-year period, form the basis of this study. These cases provide a basis for comparison of those patients currently receiving adjuvant chemotherapy with those who did not receive such treatment. Anatomic findings in 54 cases subjected to complete postmortem examinations were analyzed. Three significant findings emerged: pulmonary metastases were observed in all but one case, lymph-node metastases were found in only four cases, and in all metastases the histologic pattern reproduced that of the primary lesion. In addition, patients less than 26 years old had a significantly earlier appearance of pulmonary metastases than patients past this age. Patients with osteoblastic tumors had the poorest survival rate, followed by those with chondroblastic lesions. Those with fibroblastic tumors survived longest. In the overall study of 243 cases, tumors in the distal end of the femur and the proximal end of the tibia accounted for 147 cases, representing 60.5% of the cases. The highest incidence of the tumor was in the second decade of life, with 76.5% of the cases occurring in patients less than 25 years old. Three-year survival for the series was 21.7%, with only 12.6% surviving five years. Persons with primary lesions in the facial bones had the highest survival rate. Those with lesions in the humerus, tibia, and distal end of the femur had decreasingly lower survival rates. The lowest survival rates were for patients with lesions of the torso. In the femoral cases, size was a factor in survival; no patient with a tumor larger than 10 cm survived longer than five years. The surgery, irradiation, and chemotherapy employed--individually or in combination--did not alter appreciably the mortality rate for this tumor; only 12.6% of the patients survived five years or longer. Survivals were directly attributable to surgical procedures, including resection of pulmonary metastases. The data analyzed in this study provide a firm baseline of experience in analyzing results of treatment for osteosarcoma prior to the use of adjuvant chemotherapy, which is currently producing a vastly improved therapeuttic response.