CD8A and neoplasm: Three basic tumour-immune phenotypes have been described previously13, including (1) the inflamed/infiltrated phenotype, in which CD8+ T cells infiltrate the tumour epithelium; (2) the immune-excluded phenotype, in which infiltrating CD8+ T cells accumulate in the tumour stroma rather than the tumour epithelium and (3) the immune desert phenotype, in which CD8+ T cells are either absent or present in very low numbers.