PDCD1 and melanoma: However, in the last decade the use of targeted therapy (combination of BRAF/MEK inhibitors) for BRAF-mutant melanoma and immunotherapy–immune checkpoint inhibitors blocking programmed cell death protein 1 (PD-1) and/or cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) has transformed the treatment landscape and dramatically improved the survival rate of patients with advanced melanoma [11,12].