People should get screened for stomach cancer once every three years, a new study reports.

Stomach cancer remains as the fourth most common cancer and the second leading cause of cancer related deaths worldwide. Nearly, 700,000 people die every year due to stomach cancer.

Japan, China and Korea have the highest number of people who have this type of cancer. People in Korea are advised to go in for a stomach cancer screening once every two years after they turn 40.

"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," said Dr. Il Ju Choi, MD, PhD, of the National Cancer Center in Korea and lead author of the study.

A small camera mounted on a long flexible tube is used to detect stomach cancer. This device is used to look at the upper digestive system and this method is called upper endoscopy.

"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," Dr. Choi said.

The study included nearly 2,500 patients with gastric cancer. Researchers divided the study partients into groups based on when the cancer was first detected.

The researchers in the present study found that cancer stages were almost same between 1 and 3 years of screening interval.

According to National Cancer Institute, the overall incidence of stomach cancer in the US has declined in the past 75 years. An estimate by the National Cancer Institute states that approximately $1.6 billion is spent in the United States each year on stomach cancer treatment.

The study was published in the journal Cancer.