A simple oral rinse may provide early detection of gastric cancer, according to new findings presented by Perati et al at Digestive Disease Week (DDW) 2024 (Abstract 949) and simultaneously published in Gastroenterology.

Background

Gastric cancer is the fourth leading cause of cancer mortality across the world.

“In the cancer world, if you find patients after they've developed cancer, it's a little too late. The ideal time to try to prevent cancer is when it’s just about to turn into cancer,” stressed lead study author Shruthi Reddy Perati, MD, a general surgery resident at the Rutgers Robert Wood Johnson School of Medicine. “No formal screening guidelines for gastric cancer are available in the United States, and more than half of patients with gastric cancer receive a diagnosis when the cancer is already at an advanced stage,” she added.

Study Methods and Results

In the new study, researchers analyzed bacteria samples from the mouths of 98 patients scheduled to undergo endoscopy—30 of whom were known to have gastric cancer, 30 of whom had premalignant gastric conditions, and 38 of whom were healthy controls.

The researchers found distinct differences between the oral microbiomes of the controls compared with patients with gastric cancer and premalignant conditions. They also discovered little difference between the samples collected from the patients with gastric cancer and those with premalignant conditions—suggesting that changes in the microbiome may occur as soon as the stomach environment begins to undergo changes that can eventually develop into cancer.

Conclusions

“We were able to identify [patients] who had precancerous conditions. As a screening and prevention tool, this has enormous potential. We see that the oral microbiome and the [gut] microbiome are connected, and knowing what bugs are in your mouth tells us what the stomach environment is like,” Dr. Perati emphasized. “That has a huge implication that could lead to some practice-changing tests and guidelines,” she underlined.

The findings indicated that oral bacteria alone could serve as biomarkers for the risk of gastric cancer. After conducting their research, the researchers developed a model of the 13 bacterial genera representing the most significant differences between controls and the gastric cancer and premalignant conditions groups. They plan to conduct larger studies involving multiple institutions to ensure that their findings are generalizable to a wider population.

“Even with a small cohort, we were able to see some stark differences and believe the findings are very promising,” Dr. Perati concluded.

Disclosure: For full disclosures of the study authors, visit gastrojournal.org.