Programmed cell death protein-1 (PD-1) and its ligand (PD-L1) inhibitors are immune sentinel monoclonal antibodies, and PD-1/L1 immunotherapy has become an important treatment for cancers, such as lung cancer, melanoma, and lymphoma, and has received widespread attention in the treatment of mRCC [5]. The gene discussed is PDCD1; the disease is melanoma.