The clinicopathological significance and prognostic value of PD‐L1 in oral squamous cell carcinoma

OBJECTIVE: To investigate the relationship between the expression of PD-L1 in OSCC and the clinicopathological features and prognosis of patients. METHODS: We retrospectively analyzed the clinicopathological data and prognosis of 381 OSCC patients. Immunohistochemical staining was performed on OSCC tumor specimens, and the expression level of PD-L1 was evaluated according to the combined positive score (CPS). Kaplan-Meier analysis was used to identify the effect of PD-L1 expression and clinicopathological features on the prognosis of patients. Univariate and multivariate Cox regression analyses were conducted to determine the hazard factors affecting the prognosis of patients. RESULTS: PD-L1 overexpression was significantly associated with cervical lymph node metastasis (p = 0.018), worse clinical stage (p = 0.022), worse tumor differentiation (p = 0.046), and worse depth of invasion (DOI) (p = 0.003). Poorer clinical stage and degree of tumor differentiation were significantly associated with poorer OS and DSS in patients. PD-L1 expression was not associated with prognosis in patients with OSCC. CONCLUSIONS: High PD-L1 expression was significantly associated with higher tumor malignancy in OSCC patients. Poorer clinical stage and degree of tumor differentiation were associated with poor prognosis in OSCC patients. Our results may help clinicians develop more appropriate individualized treatment strategies for their patients, thus improving their outcomes.