East Asians are more likely to develop more aggressive stomach cancer because they are more likely to develop alcohol intolerance, according to a new study led by Japanese researchers.
The researchers’ findings, published this week in the scientific journal Nature Genetics, link lower alcohol tolerance to a higher risk of developing diffuse gastric cancer, a rarer type of stomach cancer that affects more than one area of the stomach.
Dr. William Dahut, chief scientific officer of the American Cancer Society, said the study — which collected cells from nearly 1,500 gastric cancer patients in Japan, China, South Korea, Singapore and the United States — is the first large-scale genome-wide analysis of gastric cancer.
“East Asians have an interesting combination of mutational development and a specific genotype that interferes with alcohol metabolism,” said Dahut, who was not involved in the study. “It seems that if they have this genotype, they are more likely to develop a specific tumor mutation.”
Stomach cancer has long affected the East Asian population disproportionately compared to Western countries. Half of the world’s gastric cancer cases occur in China, and it is the most common type of cancer in Japanese men. However, in the United States, stomach cancer accounts for only about 1.5% of all new cancers per year.
People of East Asian heritage are much more likely to inherit a genetic mutation not usually found in other ethnic groups that compromises the ability to metabolize alcohol. This is the same mutation that causes facial flushing after drinking, often called the “Asian glow,” study co-author Tatsuhiro Shibata said.
Shibata, who heads the Division of Cancer Genomics at the National Cancer Center Research Institute of Japan, said he hopes the findings will help researchers spot patterns in the onset of gastric cancer.
“We may develop a specific way to detect areas and maybe prevent certain cancers,” he said.
The inability of many East Asians to process alcohol properly allows it to sit in the stomach for a long time, making frequent drinkers more likely to develop chronic gastritis, said Ajay Goel, who studies gastrointestinal cancer detection at City of Hope Medical Center in California. is not involved in the new study.
“It essentially leads to chronic inflammation in the stomach,” Goel said. “And eventually, over years and years of repeated exposure, these patients tend to have an increased incidence of gastric cancer.”
Stomach cancer cases are also statistically much more common in men than in women. But this makes sense from a behavioral perspective, Goel said, rather than due to inherent genetic factors. The data show that East Asian men tend to consume significantly more alcohol than their female counterparts.
As with any cancer, early detection is crucial in the treatment of gastric cancer. But because it is relatively rare in the West compared to other types such as breast, cervical and colon cancer, gastric cancer screening is not routinely done in the United States.
“It’s increasingly important information about the power of knowing your genomics,” Dahut said.