POLD1 and colorectal cancer: Essentially, PDL1 provides a direct indication of whether a tumor sample of a colorectal cancer patient has high CD8+ T-cell infiltration, while MSI/MSS status, TMB, POLE/POLD1 mutation, and MSI-like gene signature characterize the likelihood of a tumor sample generating high neoantigen level, thus indirectly indicating whether a tumor sample of a colorectal cancer patient could potentially have high CD8+ T-cell infiltration.