Abstract
To sum up, modern resection and extremity-preserving therapy is characterized by the following aspects: (1) The surgical procedure must be appropriate for the stage of the tumor. (2) From a functional point of view, the results of the resection treatment have so far been encouraging. (3) In spite of considerable technical progress, the implantation of bone-replacement endoprostheses as a treatment for primary osteosarcoma of the extremities must sill be considered to be at the experimental stage.