Scientists Identify Hidden Risk Factors for Stomach Cancer

Researchers from Duke-NUS Medical School and the National University Health System of Singapore have found that the risk of developing stomach cancer is established long before symptoms appear. Factors influencing this risk include age, smoking, genetic changes in the blood, and even bacteria from the oral cavity. The study results were published in the journal Cancer Discovery (CanDis).

An analysis of over 1,500 samples of intestinal metaplasia—a precancerous condition of the stomach lining—showed that even at this stage, cells accumulate mutations characteristic of future tumors. Mutations in the ARID1A gene were particularly significant, as they were associated with a higher risk of progression to cancer and a worse prognosis.

The researchers also identified DNA “traces” of oxidative stress, which intensifies with smoking and increases the likelihood of malignant changes.

Another important factor is clonal hematopoiesis—age-related mutations in blood stem cells. This condition is more common in older individuals and is associated with increased vulnerability to stomach cancer. In such patients, bacteria normally found in the mouth, including Streptococcus, were detected in the stomach lining. According to the authors, the combination of age-related immune changes and chronic inflammation accelerates damage to the mucosa.

Stomach cancer does not develop from a single cause but as a result of the cumulative effect of multiple adverse factors. Understanding these hidden mechanisms can help identify at-risk groups well before disease onset and develop more effective preventive strategies.