CTLA4 and melanoma: Surgery was the gold standard of care for resectable melanoma owing to the lack of effective therapeutic agents for melanoma before the era of the development of novel therapeutic agents, such as immune checkpoint inhibitors (programmed death 1 [PD‐1] and cytotoxic T‐lymphocyte‐associated protein 4 [CTLA‐4] inhibitors) and molecular‐targeted agents (BRAF inhibitors and MEK inhibitors).