Data of all the imaging techniques with regard to detection of metastases, species delineation of the leasion, preoperative resection strategies as well as intraoperative changes of the resection strategies will be collected in a data base. Patients will be provided with care immediately after they are discharged. Therefore, every six months they will be send to our special consultation. The data we gain will subsequently be tested for statistical significance and will then be evaluated (MS Excel, SPSS). The results will be published in medical literature.