CD274 and head and neck cancer: Although immunohistochemistry for PD-L1 is utilized to identify a variety of cancers that are most likely to respond to anti-PD-1/PD-L1 therapy, including bladder cancer, breast cancer, non-small cell lung cancer, head and neck cancer, gastric cancer, esophageal and esophagogastric junction cancer, cervical cancer, and vulvar cancer, its predictive value for HCC response is questionable (8).