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Stomach cancer

Overview of stomach cancer

Stomach cancer (also called gastric cancer) is a type of gastrointestinal (GI) cancer where the cells lining the stomach become cancerous, and tumors may form. Stomach cancer is relatively uncommon, affecting approximately 27,000 Americans each year.

Early diagnosis makes it easier to treat stomach cancer. If you develop stomach cancer, quickly receiving care vastly improves the chances of successfully removing all cancer before it spreads.

If you experience any stomach cancer symptoms, or you are concerned about your risk factors, Find a Doctor near you. Our Dignity Health locations offer diagnosis, prevention, and treatment of stomach cancer.


Stomach cancer typically begins as precancerous changes that can develop into cancer slowly over time. While some of these changes are visible in diagnostic procedures such as endoscopy, they usually don’t cause any symptoms until after the cancer progresses.

Stomach cancer symptoms are usually vague, and often mimic other sources of digestive distress.

When symptoms do start to develop, they can include:

  • Abdominal pain or swelling
  • Anemia, low red blood cell count
  • Heartburn or indigestion
  • Loss of appetite or feeling full or bloated after small amounts of food
  • Nausea or vomiting that may be bloody
  • Unintended or unexplained weight loss
  • Vague discomfort in the abdomen
  • Weakness or fatigue

These symptoms are the same as other, noncancerous conditions. Noticing one or more of these symptoms does not mean you have cancer. However, you should see a doctor if symptoms do not improve or get worse. Early diagnosis is often the key to successful stomach cancer treatment.


Health experts do not know what exactly causes stomach cancer to occur in some people and not others. Still, all cancers occur when healthy cells mutate and begin to grow abnormally, causing lesions or tumors and possibly spreading throughout the body. When these cell mutations occur in the stomach, it is defined as stomach cancer.

Stomach cancers are often preceded by “precancerous changes,” or observable changes in the lining or glands of the stomach. One common precancerous change is called intestinal metaplasia, in which the cells lining the stomach start to look more like the cells lining the intestine. H. pylori infection and eating certain things such as smoked and salted, preserved foods may make these changes more likely.

If the cells lining the stomach are damaged by autoimmune response, H.pylori, or other infections, it can lead to another precancerous condition called chronic atrophic gastritis. This means the stomach glands are either shrunk or absent.

Regardless of the cause of stomach cancer, early diagnosis and treatment often lead to a better outcome.


The most common form of stomach cancer is adenocarcinoma, which starts in the gland cells lining the inside of the stomach. This form accounts for up to 95 percent of stomach cancers. Other types are very rare.

Risk factors

Certain factors may increase your risk of stomach cancer. These factors do not guarantee you will develop stomach cancer, and it is possible to have stomach cancer without any of these risk factors. However, researchers have determined that people with these risk factors have a higher likelihood on average:

  • Age older than 50 (the average age of those diagnosed with stomach cancer is 68)
  • Diet high in salted or smoked foods
  • Family history of stomach cancer
  • History of Helicobacter pylori (H. pylori) infection (H. pylori) is a bacteria that can cause stomach ulcers
  • Male gender
  • History of certain conditions, including pernicious anemia, chronic gastritis (inflammation), Lynch syndrome, invasive lobular breast cancer, and familial adenomatous polyposis
  • Obesity
  • Smoking and alcohol use


Some ways to reduce risk of stomach cancer are:

  • Not smoking
  • Discussing any digestive symptoms with your doctor as soon as possible
  • Attending regular physical checkups
  • Maintaining a healthy weight
  • Engaging in regular physical activity, as recommended by your doctor
  • Avoiding excess alcohol consumption
  • Avoiding excess consumption of pickled, salted, and smoked foods
  • Increasing consumption of vegetables and citrus fruits
  • Seeking prompt treatment for symptomatic H. pylori infection

The information contained in this article is meant for educational purposes only and should not replace advice from your healthcare provider.