Oral microbiota and cancer – what is the current state of knowledge?

Abstract

Cancer is one of the leading causes of death worldwide, and increasing evidence suggests that bacteria and the human microbiome may contribute to its development. The oral microbiome is one of the most diverse microbial communities in the body and may influence both local and systemic diseases. This review summarizes current knowledge on the relationship between oral microbiome dysbiosis and cancer, focusing on possible mechanisms, risk factors, and diagnostic potential. A structured literature review was performed using major scientific databases, including studies published between 2000 and 2026. The available evidence shows that oral microbiome alterations are associated with several types of cancer, particularly oral, digestive tract, and hematological cancers. Further research is needed to clarify whether these changes contribute directly to cancer development and whether oral microbiome assessment could be useful for cancer prevention, screening, or treatment.