Risk Factors You Should Know for Gastric (Stomach) Cancer
Judi Ebbert, PhD, MPH, RN | Nov 20, 2017
Gastric (also known as stomach) cancer doesn’t cause symptoms in the early stages – it’s usually diagnosed after it has spread to other parts of the body. And the incidence of this cancer in the U.S. isn’t high enough for total population screening to be as cost-effective as it is in countries like Japan and Chile, where there’s a higher incidence of the disease. So knowledge of risk factors is key to better outcomes – not only in the U.S., but also around the world. Here are gastric cancer risk factors you should know.
Advanced age and male sex
Cancer risk increases with age, and men face greater risk for gastric cancer than women. The reasons for increased risk in males are unclear. Some experts think estrogens may protect against gastric cancer. If estrogen is protective, a sex change from male to female, which includes hormone therapy, may reduce risk in someone who is transgender.
Race/ethnicity and socioeconomic status
Gastric cancer occurs more often in nonwhites than in whites. The highest incidence of the cancer in the United States is in Native Americans and Asians, and the highest mortality rate occurs in black men. Lower socioeconomic status indicators of increased risk are low education and low income, leading to reduced awareness and limited access to health care.
Dietary habits and tobacco use
Vividly colored, nonstarchy, leafy vegetables, and fruits may reduce risk. That’s because foods rich in vitamin C, folate, carotenoids, and phytochemicals may help inhibit cancer. Following the Mediterranean diet and eating high fiber foods appears to reduce risk of cancer. Diets high in salted, smoked, and preserved foods, however, may increase risk. Smoking tobacco products increases risk for men and women. Fortunately, people can change their dietary and smoking behaviors, thus reducing risk.
Helicobacter pylori stomach infection
Helicobacter pylori is a type of bacteria that can cause cancer by infecting the lining of the stomach. The inflammation causes acid to damage the lining of the stomach. Some people with Helicobacter pylori get stomach ulcers, which leads to diagnosis and treatment to eradicate the bacteria. Most people with Helicobacter pylori don’t get ulcers and don’t know the infection is present, exposing the stomach lining to ongoing inflammation.
Genetic risk factors for gastric cancer can be family history, inherited gene mutations, and predisposition to a condition or disease. It’s important to know risk factors not only that you can change, but also those you cannot, which you should discuss with your primary care physician. If your genetic risk is high, a physician can use barium photofluorography or endoscopy to make an early diagnosis.
Family history of stomach cancer
A person whose parents or siblings have had gastric cancer is at increased risk of developing this cancer. Why? There may be a hereditary factor not yet identified by researchers, or even a learned pattern of behaviors that increase risk for stomach cancer. The important take-away is the importance of sharing this information with a doctor for appropriate surveillance for either prevention or early diagnosis.
Hereditary non-polyposis colorectal cancer (HNPCC) (Lynch syndrome)
HNPCC is also known as Lynch syndrome. HNPCC is inherited and increases the risk for colorectal and stomach cancer. The disorder is caused by a mutation in any of the following genes: MLH1 or MSH2 as well as MH3, MSH6, TGFBR2, PMS1, and PMS2. Why is it important to understand gene involvement? One reason is because there will likely be more clinical trials in the future that target specific genes, and it’s helpful to be informed in case you need to be part of a clinical trial.
Familial adenomatous polyposis
Familial adenomatous polyposis (FAP) is an inherited disease in which extra tissue forms primarily in the large intestine and rectum. Polyps can also form in the stomach. Adenomatous polyps can become cancerous, thus increasing risk for gastric cancer. Persons with FAP or a family history of FAP should be examined regularly and have endoscopic procedures to remove the polyps to reduce risk for colon and rectal cancer as well as gastric cancer.
Hereditary diffuse gastric cancer
Another inherited condition, hereditary diffuse gastric cancer, greatly increases the risk of stomach cancer. Although the condition is rare, people with this hereditary factor have close to an 80 percent risk of getting stomach cancer. Women with this syndrome also are at risk of breast cancer. The condition is the result of mutations of the CDH1 gene.
The fungus aflatoxin
Aflatoxins may be found on corn, peanuts, cottonseed, and tree nuts. Aflatoxins flourish in warm and humid environments and can contaminate field crops not only during growth, but also during the time they are harvested and stored. Exposure to aflatoxins can result from inhalation of dust from contaminated crops and from eating the products or animals that ate contaminated feed. Aflatoxin ingestion is associated with increased risk for stomach and liver cancers.
Cells in the stomach lining make intrinsic factor (IF),which is needed to absorb vitamin B12 from food. Insufficient IF production can cause vitamin B12 deficiency, which compromises production of new red blood cells. Pernicious anemia results from insufficient red blood cells, which increases risk of stomach cancer.
Know and share risk factors with your doctor
Knowledge of risk factors is good, and modifying those that can be changed is even better. Sharing information about risk factors with a doctor is vital. Why? When your doctor is aware of increased risk factors, regular examinations can be expanded to include endoscopic procedures for early detection. Catching gastric cancer early can be life-saving.