PDCD1 and cancer: Programmed cell death-1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) are included immune checkpoint inhibitors (ICIs),[1] and programmed cell death-1 (PD-1) is the most effective immune checkpoint blocker developed in recent years.[2] Over the past 10 years, ICI has been recognized as one of the most important breakthroughs in cancer therapy.[3] There are Standards guidelines for the clinical trails of adverse events treated with PD-1 and PD-L1 inhibitors.