Therefore, combining tumor vaccines with other therapies such as PD-1/PD-L1 blockade might lead to better clinical outcomes (112), and several ongoing clinical trials are investigating the efficacy of tumor vaccines in combination with PD-1/PD-L1 blockade for the treatment of HNSCC (NCT03162224, NCT02432963, NCT03260023). This evidence concerns the gene CD274 and head and neck squamous cell carcinoma.