Immune checkpoint inhibitors (ICIs) have become the preferred first-line treatment for advanced melanoma and produce durable antitumor responses in approximately 50% of patients.1,2 ICIs targeting programmed death-1/ligand-1 (PD-1/PD-L1) prolong recurrence-free survival (RFS) when used as adjuvant therapy.3,4,5 Anti–programmed cell death-1 (anti–PD-1) also causes widespread T-cell activation and results in autoimmune side effects involving multiple organs, termed immune-related adverse events (irAEs). This evidence concerns the gene PDCD1 and melanoma.