Immune Checkpoint Inhibitors (ICIs) demonstrated good efficacy in deficient-Mismatch-Repair Microsatellite Instability-High (dMMR/MSI-H) CRC, providing clinical benefits superior to standard treatments and leading to the Food and Drug Administration (FDA) and European Medicines Agency (EMA) approval of anti-Programmed cell Death protein 1 (anti-PD-1) ICIs for the treatment of metastatic or unresectable dMMR/MSI-H CRC [6,7,8]. This evidence concerns the gene PDCD1 and colorectal carcinoma.