The overall expression of PD-L1 in the tissues examined by RT qPCR was not associated with the degree of dysplasia (grouped in high and low risk) in OLP (p = 0.521) and the differentiation (grading) (p = 0.751), the TNM classification or UICC of the OSCC (p > 0.05). This evidence concerns the gene CD274 and oral lichen planus.