Gastric cancer, also known as stomach cancer, is a type of cancer that starts in the stomach lining. Detecting the disease early can improve outcomes, but current methods are often invasive. A new study has found that the bacteria in our mouths might offer valuable insights. By analysing mouthwash samples, researchers from Rutgers Cancer Institute and RWJBarnabas Health, New Jersey’s only NCI-designated Comprehensive Cancer Center and Rutgers Robert Wood Johnson Medical School have identified unique patterns in the oral bacteria of people with gastric cancer and those with early signs of disease, compared to healthy individuals.

Lead author of the study, Haejin In, MD, MPH, MBA, FACS, FSSO, chief diversity officer, associate director for Diversity, Equity and Inclusion, and surgical oncologist at Rutgers Cancer Institute and RWJBarnabas Health, along with co-author and Rutgers Cancer Institute researcher, Brijesh Rana, BDS, MS, share more about the findings published recently in Gastrointestinal Surgery.

 Why is this topic important to explore?

Stomach cancer is often diagnosed at a late stage, leading to higher death rates globally. Early detection is key to improving survival, but there is no standard screening method in the U.S. for stomach cancer currently. Our study offers a promising solution by analysing bacteria and microbiomes in saliva/mouthwash samples, providing a non-invasive, cost-effective, and accessible way to detect stomach cancer risk early, and transforming how cancer is identified and treated. This has huge potential to save many lives since stomach cancer is deadly if not detected early.

Describe what you and your colleagues found. What are the implications of these findings?

Our study has discovered that the microbiomes in your mouth could provide clues about the health of your stomach and provide important signs about your risk for stomach cancer. By studying mouthwash samples from 98 people—30 with stomach cancer, 30 with early-stage conditions that could lead to cancer and 38 healthy individuals—our team discovered that people with stomach cancer had a very different set of bacteria in their mouths compared to healthy individuals. This finding means that we could one day use a simple, non-invasive mouthwash test to detect stomach cancer early, even before any symptoms appear. Such an approach has the potential to revolutionise early detection and improve outcomes for thousands of patients worldwide.

What are future steps pertaining to this work?

Future steps for this work include expanding the study to include a larger and more diverse group of participants to validate these findings and ensure they are generalisable across different populations. Additionally, we aim to investigate the mechanisms linking oral microbiomes to stomach health and cancer development to strengthen the biological basis of this approach.

Click here for the full study, other authors and disclosures.