CD274 and head and neck squamous cell carcinoma: In the case of squamous cell carcinoma of the head and neck (SCCHN), the “CheckMate 141” phase 3 trial demonstrated that nivolumab therapy, which inhibits the PD-l/PD-L1 and PD-L2 axis, increases the survival periods of people with recurrent/metastatic SCCHN (RMSCCHN) compared to the therapy selected by investigators3.