CD274 and cancer: The relevance in cancer of such mechanism has been best illustrated by the remarkable efficacy of anti-programmed death (ligand) 1 (anti-PD-(L)1) immune checkpoint blockers (ICB) in mismatch repair-deficient (MMRd), microsatellite-instable (MSI-H) tumours, first in the metastatic setting [5–8], and most recently in the adjuvant or neo-adjuvant settings [9, 10].