CTLA4 and sarcoma: Like other types of tumors, where research has made significant advances in the immune-therapeutic field, also for sarcomas the possible applications of immunological therapies include: (i) immunologic checkpoint blockade with the targeting of the cytotoxic T-lymphocyte associated protein-4 (CTLA-4), and of the programmed cell death protein 1 (PD-1) axis [16–31], and (ii) therapies with adoptive cell transfer [32–56].