In 2016, FDA approved the Programmed cell Death-1 (PD-1) monoclonal antibodies Nivolumab (Opdivo®, Bristol-Myer Squibb, US) and Pembrolizumab (Keytruda®, Merck & Co., Inc., US) for the treatment of HNSCC. Here, PDCD1 is linked to head and neck squamous cell carcinoma.