A new study sheds light on how often people should get screened for gastric cancer in high-risk regions of the world.

In the study, now available online ahead of print in Cancer(DOI: 10.1002/cncr.27495), the researchers note that although the incidence of gastric cancer has decreased substantially in the west, the disease remains common in areas such as Eastern Asia, including Korea, Japan, and China.

Screening for the disease is often done by upper endoscopy. To see how often the technique should be done to detect gastric cancer at an early stage, the team led by Il Ju Choi, MD, PhD, of the National Cancer Center in Korea, studied 2,485 patients who had been diagnosed with gastric cancer there. The researchers divided the patients into the following seven groups based on the interval between the endoscopy that detected gastric cancer and the endoscopy that preceded it: one year, two years, three years, four years, five years, more than five years, and never-screened.

The current recommendation in Korea is for screening every two years for individuals age 40 and older.

Gastric cancer stages were found to be similar for screening intervals between one and three years; however, the cancer stage at diagnosis was significantly higher at screening intervals of four years or more.

"The optimal screening strategy appears to be every three years. Gastric cancers are likely to become more advanced before detection with screening intervals that are longer than three years, but screening more frequently than every three years does not appear to be more beneficial," Choi said in a news release.

"The exception is if you have a family member with gastric cancer. In that case, you may need to undergo upper endoscopy screening more frequently than every three years."

The study found that patients with a family history of gastric cancer were more likely to have a higher stage at diagnosis if they had a three-year interval rather than a one-year interval.