PDCD1 and melanoma: A current trend is to combine multiple therapies, particularly a combination of anti-programmed cell death protein 1 (PD-1) and either anti-cytotoxic T lymphocyte antigen-4 (CTLA-4)12 or the newly approved ICI targeting lymphocyte-activation gene 3 (LAG-3),13 or the combination of these checkpoint inhibitors with ACT for melanoma and ovarian cancers.14,15