Can historical controls be used in current clinical trials in osteosarcoma? Metastases and survival in a historical and a concurrent group

A historical group consisting of 35 patients with osteosarcoma (preceding paper) was compared to a concurrent group of 23 patients. The treatment for the primary tumors differed only slightly in the two groups. Neither of the groups received adjuvant therapy. A more active approach was adopted for treatment of pulmonary metastases in the concurrent group. All the patients were followed for at least 2.5 years. The percentage of patients not developing metastases and the survival rate in the historical group were approximately one half those for the concurrent group. An analysis of prognostic factors disclosed differences between the two groups as regards the size and histological type of the tumor.