Stomach Cancer Causes and Risk Factors

Stomach (gastric) cancer begins in the innermost lining (mucosa) of the stomach. An important component of the gastrointestinal (GI) tract, the stomach is a muscular, pouch-like organ that aids digestion by mixing food with digestive juices secreted by the mucosa and then churning the mixture into a thin liquid. The partially digested food then passes into the small intestine.

Stomach cancer is relatively rare, accounting for approximately 1.5% of new cancers diagnosed in the United States each year.

What causes stomach cancer?

Scientists believe stomach cancer may develop when cancer-causing substances in consumed food come in contact with the mucosa. Another possible cause is chronic inflammation of the mucosa, which may result from an abnormally sustained immune system response. Both can trigger harmful DNA changes in the mucosal cells that promote uncontrolled cell growth, leading to the formation of a tumor.

What are the risk factors for stomach cancer?

Risk factors characteristics, behaviors and exposures that can increase the risk of—but do not directly cause—gastric cancer. Some risk factors can be controlled, but others cannot.

Stomach cancer risk factors that can be controlled

By making healthy lifestyle changes, it may be possible to control certain stomach cancer risk factors, such as:

• Poor nutrition – A diet high in smoked, pickled, fermented, salted or preserved foods is a major risk factor for stomach cancer.
• Helicobacter pylori (H. pylori) infection – A bacterium that causes stomach inflammation and ulcers, H. pylori can be effectively treated with antibiotics.
• Obesity – Carrying excess body fat increases the likelihood of stomach inflammation and cancer.
• Tobacco and alcohol use – Smoking and excessive consumption of alcoholic beverages are well-established risk factors for many types of cancer, including gastric cancer.
• Occupational exposures – Individuals who work in dusty or high-temperature processing environments and those who are exposed to certain industrial chemicals, such as chromium, are at heightened risk for developing stomach cancer.

Stomach cancer risk factors that cannot be controlled

Certain stomach cancer risk factors cannot be controlled, such as:

• Advanced age – Most cases are diagnosed after age 55.
• Family history – Individuals with a close relative who was diagnosed with gastric cancer are at increased risk.
• Inherited cancer predisposition syndromes – Hereditary diffuse gastric cancer (caused by CDH1 gene mutation), familial adenomatous polyposis (FAP), Li-Fraumeni syndrome, Lynch syndrome, juvenile-polyposis syndrome, Peutz-Jeghers syndrome and hereditary breast and ovarian cancer syndrome have been conclusively linked to stomach cancer.
• Certain medical conditions – Atrophic gastritis and intestinal metaplasia, which caused cells in the lining of the upper GI tract to mimic intestinal cells, and pernicious anemia, stomach polyps and achlorhydria are strongly associated with chronic stomach inflammation and thinning of the mucosa.
• Prior stomach surgery – If a portion of the stomach is surgically removed, the risk of gastric cancer increases.

Can stomach cancer be prevented?

By addressing known risk factors that are controllable, such as consuming a healthy diet, avoiding tobacco use and managing an H. pylori infection, it may be possible to reduce the risk of developing stomach cancer. Additionally, uncontrollable risk factors, such as advanced age and genetics, can inform more vigilant monitoring and early detection strategies.

Frequently asked questions (FAQs) about stomach cancer causes and risk factors

The following FAQs-related article provides additional information about stomach cancer causes and risk factors:

• What is the No. 1 risk factor for stomach cancer?

Benefit from world-class care at Moffitt Cancer Center

Moffitt is a National Cancer Institute-designated Comprehensive Cancer Center on the leading edge of stomach cancer research. Through our robust clinical trials program, we are continually advancing the screening, diagnostic and treatment options for this serious and uncommon condition.

If you would like to learn more about stomach cancer causes and risk factors, you can request an appointment with a specialist in Moffitt’s renowned Gastrointestinal Oncology Program by calling 1-888-663-3488 or submitting a new patient registration form online. We do not require referrals.