CD274 and skin squamous cell carcinoma: PD-L1 positivity in 26.5% of cSCC cases with a cutoff value of ≥1% and 10.3% positivity with a cutoff value of ≥5% were reported by Schaper et al. Their study also indicated a positive correlation between the intensity of inflammation accompanying the tumor and the PD-L1 expression in both tumor cells and tumor-infiltrating lymphocites [44].