Mouthwash sample shows promise for early detection of deadly cancers, study finds

A recent study indicates that oral bacteria collected through mouthwash may aid in the early detection of specific cancers using a straightforward, non-invasive sample. The research, conducted by South Korean scientists, analyzed mouth and stool samples from over 500 individuals, including healthy subjects, those with metabolic disorders like diabetes and high blood pressure, and patients with stomach and colorectal cancer.

The scientists developed an indicator called the mouth-fecal similarity index (MF) to measure the similarity between bacteria present in the mouth and those in the gut. The study found that patients with stomach and colorectal cancer exhibited distinct microbial patterns and significantly higher MF values compared to individuals with metabolic disorders.

These results were comparable to the fecal occult blood test, a standard screening method for colorectal cancer. The mouthwash samples showed a higher capacity to differentiate between cancer patients and healthy individuals across various groups. The researchers noted that while the link between microbial indicators and cancer persisted even after considering lifestyle factors, such as alcohol consumption and body mass index, further studies are needed to confirm these findings and explore whether bacterial transfer between the mouth and gut contributes to cancer development or is a consequence of the disease.

The team emphasized that the method is still in the research phase and requires additional clinical trials before it can be widely adopted. If confirmed, a simple mouth rinse with mouthwash could potentially serve as an easy, minimally invasive option for early screening of certain gastrointestinal cancers.