Review of emerging biomarkers in head and neck squamous cell carcinoma in the era of immunotherapy and targeted therapy

Background Biomarkers in head and neck squamous cell carcinoma (HNSCC) emerge rapidly in recent years, especially for new targeted therapies and immunotherapies. Methods Recent, relevant peer‐reviewed evidence were critically reviewed and summarized. Results This review article briefly introduces essential biomarker concepts, including purposes and classifications (predictive, prognostic, and diagnostic markers), and the phases of biomarker development. We summarize current biomarkers in order of clinical utility; p16 and human papillomavirus status remain the most important and validated biomarkers in HNSCC. The rationale for biomarker study design continues to evolve with technological advances, especially whole‐exome or whole‐genomic sequencing. Noninvasive body fluid and liquid biopsy biomarkers appear to hold strong potential for development as tools for early cancer detection, cancer diagnosis, monitoring of disease recurrence, and outcome prediction. In light of discrepancies among different technologies, standardized approaches are needed. Conclusion Biomarkers from cancer tissue or blood in HNSCC could direct new anticancer therapies.