CD8A and cancer: For instance, CD8+ T-cell infiltration is equivalent between lung metastases from colorectal cancer and renal cell carcinoma, but NK cells are more abundant and prognostic indicators in renal cell carcinoma lung metastasis.137 The immune contexture of primary and secondary tumours can also be analogous with regards to immunologically silent or active microenvironments as, across multiple cancer types, immune active primary tumours are more likely to generate immune active metastases.138 However, the immune landscape might also very well look different between primary and secondary tumours.