Antibodies against cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), programmed cell death protein 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) are important state-of-the-art treatments, particularly for patients with metastasized skin cancer. The gene discussed is PDCD1; the disease is skin neoplasm.