114 patients with osteosarcoma in the extremities had been reported to the SSG II trial, 132 to the SSG VIII trial and, until October 1998, 99 to the ISG/SSG I trial. The SSG IV trial included 53 patients and the SSG IX trial 104 patients until October 1998. In the SSG II trial, 19% were good responders (grades III and IV) as compared to 51% in the SSG VIII trial. On reevaluation was the response changed in one forth of the cases in both the SSG II and SSG VIII trials. In 9 and 10 cases (8%), respectively, the reevaluation resulted in a change from "good responder" to "bad responder". In the ISG/SSG I trial, the preliminary results showed a good response in 22% of the cases. In the SSG IV trial, 44% were good responders (grades III and IV), as compared to 54% in the SSG IX trial.