As clinical development of TIGIT/CD155-directed therapies progresses, a more precise understanding of how TIGIT and CD155 expression relates to clinically relevant mutations in CRC, including KRAS, NRAS, BRAF, and PIK3CA mutations, and to key features of the TME will be crucial for the implementation of personalized treatment strategies. The gene discussed is NRAS; the disease is colorectal carcinoma.