PDCD1 and metastatic melanoma: A 48-year-old gentleman with metastatic melanoma currently receiving the cytotoxic T-lymphocyte–associated antigen 4 (CTLA-4) inhibitor, ipilimumab (Yervoy), and the programmed cell death protein 1 (PD-1) inhibitor, nivolumab (Opdivo), returned for evaluation prior to receiving cycle 2.