PDCD1 and melanoma: In recent years, immune checkpoint inhibitor (ICI) targeting PD‐1/PD‐L1 (programmed cell death 1/programmed cell death 1 ligand 1) and CTLA‐4 (cytotoxic T‐lymphocyte antigen‐4) have become the most revolutionary treatment in several malignant neoplasms such as non‐small cell lung cancer (NSCLC) and melanoma.7 Sex hormones regulate the expression and function of PD‐1/PD‐L1 and affect the PD‐1 pathway in mediating autoimmunity.8, 9 Based on existing knowledge of published trials, male patients seemed to benefit more from immune checkpoint inhibitors.