Advanced penile SCC (PSCC) is a rare diagnosis and carries a grim prognosis as patients who experience distant metastases are unlikely to live more than two years. There is very limited evidence to guide systemic treatment of advanced PSCC. Standard first-line treatment of advanced PSCC is paclitaxel, ifosfamide, and cisplatin (TIP). Optimal second-line or later treatment is unknown, and an unmet need exists for novel second-line or later treatments. Studies of PSCC tumor tissue found that 40-62% of PSCC cases express ≥ 1% programmed death-ligand 1 (PD-L1) on tumor cells or infiltrating immune cells.1-4 Thus, there has been interest in the efficacy of programmed cell death protein 1 (PD-1) or PD-L1 immune checkpoint inhibitors for advanced PSCC.