To definitely asses such molecular markers in musculoskeletal tumors they have to be identified in human patient samples with corresponding tumors, before molecular markers can be validated in animal models. Just because these soft tissue and bone tumors are rare (compared to breast and lung carcinomas), it is of great importance that samples from all patients treated at Balgrist University Hospital are collected systematically und stored correspondingly. Only like this valid statements can be done. Therefore the investigators intent to collect tissue and blood samples from all patients who agree in participating in the study. The samples will be taken during routine biopsies and operations. To compare tumor tissue and healthy tissue it is also planed to take samples from tumor free patients who undergo a knee replacement surgery. The investigators would store the surgical waste and involve these samples in the analyzes.