Impact of the Microbiome on Onset and Prognosis of Oropharyngeal Squamous Cell Carcinoma

Introduction Recent attention to the role of the microbiome in oral cancer has prompted investigations into its potential contribution to oropharyngeal squamous cell carcinoma (OPSCC), given their anatomical and immunological overlap. However, consistent microbial patterns have not been identified across studies. Methods A systematic review, following PRISMA guidelines, examined studies on the role of the oral/oropharyngeal microbiome in OPSCC development, including its statistical relevance in cancer occurrence and prognosis. Results From 131 articles (2017–2025), 19 involving 4502 patients were analyzed. Increases in Porphyromonas gingivalis , Tannerella forsythia , and Fusobacterium were noted in OPSCC patients. However, no bacterial taxa were reproducibly identified across all studies, reflecting substantial heterogeneity and limited overlap. Conclusion HPV, smoking, and cancer affect microbiota composition. The absence of reproducible microbial signatures highlights the need for more standardized, large‐scale, and mechanistically driven studies to clarify the microbiome's role in OPSCC.