CD8A and cancer: Tumour microenvironment (TME) comprises diverse cells types, including cancer stromal cells, fibroblasts, lymphocytes, granulocytes, macrophages, mast cells (MCs), natural killer cells (NKs), dendritic cells (DCs) and myeloid‐derived suppressor cells (MDSCs).3 In most cases, the presence of B lymphocytes, cytotoxic CD8‐positive T lymphocytes, NKs, ‘M1‐like’ macrophages and high numbers of DCs are indicative of a favourable outcome.