A sarcoma is a cancer arising from transformed cells of mesenchymal origin. Sarcomas are a family of rare cancers, encompassing a huge variety of histological subgroups, and their immunogenicity varies substantially across histologies, with discrepant mutational loads, specific antigenic expressions, and immune contextures. Malignant tumors made of cartilage, cancellous bone, muscle, fat, vascular, or hematopoietic tissues are considered sarcomas. Surgery is important in the treatment of most sarcomas. Additional treatments may include chemotherapy and radiation therapy, which can be administered before and/or after surgery. Chemotherapy significantly improves the prognosis of many patients with sarcomas, especially those with bone sarcomas.