Betel-nut chewing does not influence PD-L1 expression rates in recurrent/metastatic head and neck squamous cell carcinoma (HNSCC): A prospective biomarker prevalence study.

This study explored the relationship between betel-nut chewing and programmed death-ligand 1 (PD-L1) expression in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) patients in Taiwan. A total 280 R/M HNSCC patients, predominantly male, were evaluated; 75.4 % of whom chewed betel-nut. The prevalence of PD-L1 expression (combined positive score ≥1) was 94.3 % with similar PD-L1 expression rates between betel-nut-exposed and non-exposed groups. PD-L1 prevalence did not differ in those who received prior first-or second-line systemic therapy. In summary, betel-nut exposure did not notably affect PD-L1 expression rates in R/M HNSCC patients in Taiwan.