CD274 and head and neck squamous cell carcinoma: Considering the recent approval of anti‐PD‐1/PD‐L1 antibodies (pembrolizumab and nivolumab) for HNSCC as a first‐line treatment in recurrent and metastatic disease by the United States of America Food and Drug Administration, new treatment options for HNSCC are available and have shown promising results.66, 67