Together with the relatively minor populations of macrophages and dendritic cells (DCs) [10], TILs exert influence on the behaviour of cancer cells and play a deterministic role in the course of cancer development through a myriad of adaptive immune responses, which are believed to be initiated by tumour-specific peptides known as neoantigens or tumour-associated antigens (TAAs) that have arisen as a result of expressed somatic cancer mutations [11], and are presented to effector cells of the immune system by complexing with major histocompatibility complex (MHC) proteins. This evidence concerns the gene HLA-C and cancer.