CD274 and cancer: Immune escape of cancer cells caused by regulatory T cells and immunosuppressive (M2) macrophages has moreover been recognised to contribute to cancer prognosis.21–23 Common lymph endothelial and vascular endothelial receptor-1 (Clever-1) is a multifunctional adhesion and scavenger receptor expressed by M2 macrophages.21 Similar to high tumour PD-L1 expression, M2 macrophage infiltrate may inhibit T cell response causing increased immune tolerance and poorer prognosis.17