Although T cells are abundant in the stroma of human primary PDAC, and patients with higher levels of CD4+ and/or CD8+ T cells have significantly prolonged survival, most PDACs develop an immunosuppressive microenvironment that restricts the infiltration of anti-tumour T cells.46,49 In this regard, differential immune cell recruitment could be reflective of distinct immunosuppressive mechanisms. This evidence concerns the gene CD8A and neoplasm.