from the NCI PDQ (Physician Data Query)
Gastric cancer is a disease in which malignant (cancer) cells form in the lining of the stomach.
The stomach is a J-shaped organ in the upper abdomen. It is part of the digestive system, which processes nutrients (vitamins, minerals, carbohydrates, fats, proteins, and water) in foods that are eaten and helps pass waste material out of the body. Food moves from the throat to the stomach through a hollow, muscular tube called the esophagus. After leaving the stomach, partly-digested food passes into the small intestine and then into the large intestine.
The wall of the stomach is made up of 3 layers of tissue: the mucosal (innermost) layer, the muscularis (middle) layer, and the serosal (outermost) layer. Gastric cancer begins in the cells lining the mucosal layer and spreads through the outer layers as it grows.
Stromal tumors of the stomach begin in supporting connective tissue and are treated differently from gastric cancer. See the PDQ summary on Gastrointestinal Stromal Tumors Treatment for more information.
For more information about cancers of the stomach, see the following PDQ summaries:
Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. Talk with your doctor if you think you may be at risk. Risk factors for gastric cancer include the following:
These and other symptoms may be caused by gastric cancer. Other conditions may cause the same symptoms.
In the early stages of gastric cancer, the following symptoms may occur:
In more advanced stages of gastric cancer, the following symptoms may occur:
Check with your doctor if you have any of these problems.
The following tests and procedures may be used:
One or more of the following tests may be done on the samples of tissue that are removed:
Certain factors affect prognosis (chance of recovery) and treatment options.
When gastric cancer is found very early, there is a better chance of recovery. Gastric cancer is often in an advanced stage when it is diagnosed. At later stages, gastric cancer can be treated but rarely can be cured. Taking part in one of the clinical trials being done to improve treatment should be considered. Information about ongoing clinical trials is available from the NCI Web site.