This is because immune‐mediated tumour cells removal involuntarily puts evolutionary pressure on tumour cells to mutate further and generate variants efficient in evading immune responses by either down‐regulating pro‐immunogenic features (such as expression of HLA molecules) or up‐regulating immunosuppressive factors, for example, immune checkpoint receptors and ligands, such as PD‐L1 and CTLA4. Here, CTLA4 is linked to neoplasm.