PDCD1 and cancer: The fact that CMS1 cancers display a large immune infiltrate, including CD8+ cytotoxic T lymphocytes, CD4+ activated Type 1 T helper cells (Th1), and natural killer cells, makes these tumors potentially susceptible to monoclonal antibody targeting of PD‐1/Programmed cell death‐ligand 1 (PD‐L1) [28, 29, 30, 31]; however, it is important to remember that the anti‐PD‐L1 therapies in CRC are currently chosen on the basis of mismatch repair‐deficient(dMMR)/MSI‐H status rather than CMS subtyping.