Possibility of early detection of gastric cancer through oral microbiome testing

New evidence suggests that mouthwashes used to determine oral microbiome composition may serve as an early detection tool for stomach cancer.

Researchers found distinct differences in bacterial composition in patient samples, indicating that oral microbial signatures may be used as biomarkers to assess gastric cancer risk.

“Too many patients are diagnosed too late. There are no formal screening guidelines for gastric cancer, and more than half of gastric cancer patients are not diagnosed until the cancer is already at an advanced stage.” said Shruti Reddy Perati. He is a general surgery resident at Rutgers University Robert Wood Johnson School of Medicine in New Brunswick, New Jersey.

Currently, detection of gastric cancer requires invasive procedures such as endoscopy. Therefore, a non-invasive “swish-and-spit” test could be more accessible and allow for broader screening, Perati said, adding that her research (Abstract 949) suggests that the number of gastrointestinal diseases in 2024 He said this at a May 8 press conference previewed for the Week (DDW).

stomach canceralso known as stomach cancerit is 4th most common cause Number of cancer-related deaths worldwide. According to the American Cancer Society, there will be 26,890 new cases and 10,880 deaths from this type of cancer in the United States in 2024. Estimate.

Characteristics of microorganisms discovered

Perati et al. collected oral rinse samples from 98 patients. Of these, 30 had known gastric cancer, 30 had a precancerous gastric condition (provincestric cancer), and 38 were control participants without forestomach or stomach cancer. 62% were female, 32% were Hispanic, 31% had diabetes, and 18% were smokers.

The researchers analyzed the samples for alpha and beta diversity and conducted differential analysis using a framework called microbiome composition analysis.

They found clear differences between the oral microbiome of the healthy group and the oral microbiome of the gastric and forestomach cancer groups. Additionally, the microbiomes of cancer patients and precancerous participants were similar.

This result suggests that changes in the microbiome occur as soon as the stomach environment begins to change, and may eventually lead to cancer.

“The oral microbiome may serve as a window into the composition of the gastric environment,” Perati says.

The researchers created a screening model to detect the 13 most relevant bacterial genera that differed between the control group and the gastric cancer and pre-gastric cancer groups. The 10-fold cross-validation model showed good discriminatory power using only bacteria (area under the curve) [AUC]0.74), which was further improved by adding clinical variables such as demographics and comorbidities (AUC, 0.91), the researchers noted.

Additional considerations

Microbiomes can change between people and within the same individual over time. Probiotics, antibiotics and diet can cause changes in the microbiome, Perati said.

When asked how these changes might affect the accuracy of oral hygiene tests, Pelati said, “In general, dietary changes affect the diversity and prevalence of specific bacteria throughout the gastrointestinal tract. It is known that it can give

Differences are expected, but the hope is that the differences in microbiome composition between the malignant and control groups will be more significant than low-level background changes due to dietary modifications, for example, he added. .

Perati said the research is still in its early stages and the results need to be validated in larger studies.

Still, she said the study has “huge implications that could ultimately lead to the development of non-invasive, accessible early screening for gastric cancer.”

Mr. Perati did not report any relevant financial relationships. This research was supported independently.

Damian McNamara I'm a staff journalist based in Miami. It covers a wide range of specialties, including infectious diseases, gastroenterology, and emergency medicine. Follow Damian on X/Twitter: @MedReporter.