Tumor immunotherapy can be performed in different ways: cellular immunotherapies (adoptive cellular immunotherapy (ACI), NK cell therapy, chimeric antigen receptor T-cell (CAR-T) immunotherapy, immune checkpoints inhibitors (PD-1 ICIs, PD-L1 ICIs, CTLA-4 ICIs), oncolytic viruses, vaccines (tumor cell vaccines, genetic vaccines, dendritic cell vaccines, protein/peptide-based vaccines, in situ vaccines, neoantigen vaccines) and others (targeting myeloid derived suppressor cells, cytokine gene therapy, targeting tumor microenvironment, oncolytic peptides). This evidence concerns the gene CTLA4 and neoplasm.