POLD1 and metastatic colorectal cancer: Immune checkpoint inhibitors for POLE or POLD1 proofreading-deficient metastatic colorectal cancer (retrospective, n=27), ORR compared to dMMR/MSI-H metastatic colorectal cancer 89% versus 54%, improved PFS (HR 0.17, 95% CI 0.04–0.69) and OS (HR 0.24, 95% CI 0.06–0.98) [1] and other entities [56]