Individuals who have recently been diagnosed with stomach cancer may be struggling with the news, but understanding and identifying possible stomach cancer causes can help in developing a plan and moving forward.

According to the American Cancer Society, there are numerous potential causes of cancer including genetics, age, and lifestyle. Although these risk factors and causes cannot be changed, other environmental causes can be avoided or identified when struggling with a new stomach cancer diagnosis.

Inherent risk factors are stomach cancer causes that cannot be changed. For example, stomach cancer is more common in women and in certain regions and ethnicities. Additionally, genetic risk factors can be stomach cancer causes including inherited cancer syndromes, hereditary gastric cancer, Lynch syndrome, and other genetic markers or syndromes which increase risk. However, some lifestyle factors which may contribute to stomach cancer causes can be changed including tobacco use, diet, and being overweight.

Although scientists have identified numerous risk factors for stomach cancer, the exact mechanism through which stomach lining becomes cancerous is not fully understood. One recently identified risk factor is the use of PPI drugs.

PPI (proton pump inhibitor) drugs are widely available drugs often used to treat heartburn, acid reflux, and other stomach problems. Common brands in the United States include Nexium and Prilosec. These drugs are designed to prevent damage to the stomach lining which may cause peptic ulcers.

Although the management of acid reflux is thought to reduce the risk of stomach cancer, researchers at the Centre for Translational Microbiome Research at the Karolinska Institute in Sweden recently sought to investigate the risk factors associated with PPI drugs. The study, which was the largest PPI drug study to date, studied around 800,000 adults in Sweden who used PPI drugs regularly.

“For people with reflux, we expected a higher risk of esophageal cancer, since even with treatment, the risk of cancer will probably remain higher than someone who never had reflux,” the researchers wrote in a Science Trends article. “Yet, our findings also suggested that the risk of these cancer types may be higher among those using PPIs to protect their stomach and had no reported stomach problems”.

Although the exact link between PPI drug usage and stomach cancer causes is not well understood, other researchers and studies have found similar results supporting the potential link.

“Since other groups have been publishing findings similar to ours assessing the risks related long-term PPI use, considering stomach cancer and also other cancer types but also other long-term effects, there is certainly smoke, but we are not sure yet that there is a fire,” the researchers wrote.

The researchers recommend further investigation and, in the meantime, potentially limiting the widespread use of PPI drugs. Rather than uncontrolled over the counter use, the researchers recommend limiting indications or restricting the amount of time individuals are taking PPI drugs until the potential effect on stomach cancer causes is better understood.

“So we certainly do not recommend to stop any PPI treatment without consulting a physician. Yet, we do want to raise awareness about potential long-term effects and uncontrolled over-the-counter use”.