Sarcoma comprises of a diverse family of malignancies with many histological subtypes and molecular aberrations. However, first-line sarcoma treatment options are still limited to surgery and chemotherapy which remain mostly ineffective, necessitating novel treatment strategies. Our sarcoma tumor homografts preserve original GEMM tumor histo- and molecular pathology as well as a relevant TME and are ideally positioned to test novel cross reactive or surrogate agents as well as combination strategies with checkpoint inhibitors.