M. Rebelatto, J. Walker et al., Development of a programmed cell death ligand-1 immunohistochemical assay validated for analysis of non-small cell lung cancer and head and neck squamous cell carcinoma, Diagnostic Pathology (2016), 11:95, DOI 10.1186/s13000-016-0545-8. This evidence concerns the gene CD274 and head and neck squamous cell carcinoma.