In this regard, new advances in immunotherapies with immune checkpoint inhibitors (ICIs), including drugs targeting the programmed death receptor 1 (PD-1) or its ligand 1 (PD-L1) and cytotoxic T lymphocyte associated protein 4 (CTLA-4), has revolutionized the oncology field and afforded patients with various types of cancer the potential for long-term survival (2). This evidence concerns the gene CTLA4 and cancer.