Screening people in high-risk groups for infection with H pylori and treating them could play a key role in reducing the burden of stomach cancer in these populations.
—Rolando Herrero, MD
A new report from the International Agency for Research on Cancer (IARC), an agency of the World Health Organization, urges health authorities of countries with high stomach cancer burden to include stomach cancer in their national cancer control programs and allocate more resources to control the disease.
A Working Group of international experts convened by IARC reviewed evidence to evaluate strategies for stomach cancer prevention based on the eradication of Helicobacter pylori, a bacterium that is the primary cause of stomach cancer.
The Working Group’s report “Helicobacter pylori Eradication as a Strategy for Preventing Gastric Cancer” is accessible free of charge on IARC’s website, and its recommendations are summarized in a Viewpoint article published recently in JAMA.1
“Although stomach cancer is the third most common cause of cancer death worldwide, until now it has not been given the attention it deserves,” explains Rolando Herrero, MD, Head of the Prevention and Implementation Group at IARC. “We know the main cause of the disease, which is a bacterium that can be treated with antibiotics. Screening people in high-risk groups for infection with H pylori and treating them could play a key role in reducing the burden of stomach cancer in these populations.”
A Neglected Cancer
Stomach cancer is particularly common in low- and middle-income countries and is more frequent among the most deprived populations but, with few exceptions, there are no public health programs for its prevention.
In 2012, almost 1 million new cases occurred worldwide. The majority of these occurred in East Asia, and nearly one-half occurred in China. Relatively high rates of stomach cancer have also been reported in Latin America and eastern Europe.
Stomach cancer is usually diagnosed at advanced stages, and survival rates are therefore low in most geographical areas. This makes the disease the third leading cause of cancer death globally, with an estimated 723,000 deaths in 2012. Although incidence rates are declining, the numbers of cases and deaths will remain high for decades due to growth and ageing of the global population.
H pylori Eradication as a Strategy for Preventing Stomach Cancer
H pylori has been classified by IARC as carcinogenic to humans (group 1) and is considered to be the cause of 80% of all stomach cancers. Several trials have shown that H pylori treatment is effective in preventing a significant fraction of stomach cancers, but uncertainties remain about the feasibility and impact of population-based stomach cancer prevention programs based on antibiotic treatment of the infection.
The Working Group recommended that countries explore the introduction of population-based H pylori screening and treatment programs to reduce stomach cancer incidence. The implementation and modalities of these programmes should be based on local considerations of disease burden, competing health priorities, and cost–effectiveness analyses.
The experts strongly recommended that national health authorities in high-incidence countries consider conducting demonstration programmes of H pylori screening and eradication using designs that provide a comprehensive assessment of programme effectiveness and potential risks.
“Unless effective control measures are established, thousands of unnecessary deaths will continue to occur each year. Ignoring stomach cancer in the hope that it will soon disappear on its own is not a tenable health policy,” says Christopher Wild, MD, Director of IARC. “Evaluation of the implementation of large population-based programmes of H pylori screening and treatment is now a priority and provides the potential means of preventing deaths from this lethal cancer.” ■
1. Working Group Report: IARC Helicobacter pylori Working Group (2014). Helicobacter pylori Eradication as a Strategy for Preventing Gastric Cancer. Lyon, France: International Agency for Research on Cancer (IARC Working Group Reports, No. 8). Available at http://www.iarc.fr/en/publications/pdfs-online/wrk/wrk8/index.php
2. Herrero R, Parsonnet J, Greenberg ER: Prevention of gastric cancer. JAMA. September 24, 2014 (early release online).