Stomach Cancer Causes Epidemiology

Understanding stomach cancer epidemiology–the study of diseases across populations–can help researchers learn more about the exact causes of stomach cancer. It can also help experts identify stomach cancer risk factors, so those at high risk for the disease can opt for regular screening.

While stomach cancer is rare in the United States, it’s the second leading cause of cancer death for both men and women worldwide, according to the World Health Organization (WHO) (2003). In the U.S., gastric cancer is the seventh leading cause of cancer deaths.

Unlike many cancers, stomach cancer rates are declining worldwide, a fact that WHO attributes largely to the refrigerator, which preserves fish and meat without salting.

Stomach Cancer Statistics

Stomach cancer is the fourth most common cancer in the world, after lung, breast and colorectal cancer. More than 70 percent of stomach cancers occur in developing countries, and 50 percent occur in Eastern Asia (WHO, 2003).

In 2008, The International Agency for Research on Cancer reported that 988,000 cases of stomach cancer were diagnosed worldwide, and only 21,000 of those were in the United States, while 463,000 were in China. China has the most cases of stomach cancer in the world; however, the highest rate of stomach cancer occurs in Japan, although the rate has been decreasing in recent years. Japan has put an aggressive early screening program in place that has increased cancer survival rates in recent years.

Stomach cancer survival rates vary around the world. The highest death rates in 2008 were in Eastern Asia (28.1 deaths for each 100,000 men and 13.0 deaths for each 100,000 women). The lowest death rates were in Northern America (2.8 per 100,000 in men and 1.5 per 100,000 in women). Death rates were also high in Central and Eastern Europe, and in Central and South America. Stomach cancer survival rates are highest in the United States.

Stomach Cancer Risk Factors

Some research has indicated that stomach cancer rates are so high in Eastern Asia because of the prevalence of salted foods. In particular, researchers speculate that the high occurrence of both stomach cancer and stroke in Japan is related to the high consumption of salt.

Another stomach cancer risk factor believed to lead to stomach cancer in developing countries is infection with the bacterium Helicobacter pylori (H. pylori).

Resources

International Agency for Research on Cancer. (2010). Stomach cancer incidence and mortality worldwide in 2008 summary. Retrieved February 7, 2011, from http://globocan.iarc.fr/factsheets/cancers/stomach.asp

Mayo Clinic. (2009). Stomach cancer – Prevention. Retrieved February 7, 2011, from http://www.mayoclinic.com/health/stomach-cancer/DS00301/DSECTION=prevention

National Cancer Institute. (2009). A snapshot of stomach (gastric) cancer. Retrieved February 7, 2011, from http://www.cancer.gov/aboutnci/servingpeople/stomach-snapshot.pdf

World Health Organization. (2003). Global cancer rates could increase by 50% to 15 million by 2020. Retrieved February 7, 2011, from http://www.who.int/mediacentre/news/releases/2003/pr27/en/