Key Points for This Section

Stomach cancer is a disease in which malignant (cancer) cells form in the lining of the stomach. Stomach cancer is less common in the United States than in the developing world. Older age and certain chronic conditions increase the risk of developing stomach cancer.

Stomach 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.

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The stomach and esophagus are part of the upper digestive system.

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. Stomach cancer begins in the cells lining the mucosal layer and spreads through the outer layers as it grows.

Stomach cancer is less common in the United States than in the developing world.

Stomach cancer is the fourteenth most frequent cause of cancer death in the United States. This type of cancer is much more common in many parts of Europe, Asia, and Central and South America, and is a major cause of death in the developing world.

Stomach cancer rates in the United States have greatly decreased since 1930. The reasons for this are not known, but may have to do with better food storage or changes in the diet, such as lower salt intake.

Older age and certain chronic conditions increase the risk of developing stomach cancer.

Anything that increases the chance 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. People who think they may be at risk should discuss this with their doctor. Risk factors for stomach cancer include the following:

• Having any of the following medical conditions:
  • Helicobacter pylori (H. pylori) infection of the stomach.
  • Chronic gastritis (inflammation of the stomach).
  • Pernicious anemia.
  • Intestinal metaplasia (a condition in which the normal stomach lining is replaced with the cells that line the intestines).
  • Familial adenomatous polyposis (FAP) or gastric polyps.
• Being older or male.
• Eating a diet high in salted, smoked foods and low in fruits and vegetables.
• Eating foods that have not been prepared or stored properly.
• Smoking cigarettes.
• Having a mother, father, sister, or brother who has had stomach cancer.

Glossary Terms

The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

A sugar molecule. Carbohydrates can be small and simple (for example, glucose) or they can be large and complex (for example, polysaccharides such as starch, chitin or cellulose).

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

A disease or condition that persists or progresses over a long period of time.

The things a person eats and drinks.

The organs that take in food and turn it into products that the body can use to stay healthy. Waste products the body cannot use leave the body through bowel movements. The digestive system includes the salivary glands, mouth, esophagus, stomach, liver, pancreas, gallbladder, small and large intestines, and rectum.

The muscular tube through which food passes from the throat to the stomach.

FAP. An inherited condition in which numerous polyps (growths that protrude from mucous membranes) form on the inside walls of the colon and rectum. It increases the risk for colorectal cancer. Also called FAP and familial polyposis.

Having to do with the stomach.

Inflammation of the lining of the stomach.

H. pylori. A type of bacterium that causes inflammation and ulcers in the stomach or small intestine. People with H. pylori infections may be more likely to develop cancer in the stomach, including MALT (mucosa-associated lymphoid tissue) lymphoma. Also called H. pylori.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

Redness, swelling, pain, and/or a feeling of heat in an area of the body. This is a protective reaction to injury, disease, or irritation of the tissues.

Having to do with the intestines.

The long, tube-shaped organ in the abdomen that completes the process of digestion. The intestine has two parts, the small intestine and the large intestine. Also called the bowel.

The long, tube-like organ that is connected to the small intestine at one end and the anus at the other. The large intestine has four parts: cecum, colon, rectum, and anal canal. Partly digested food moves through the cecum into the colon, where water and some nutrients and electrolytes are removed. The remaining material, solid waste called stool, moves through the colon, is stored in the rectum, and leaves the body through the anal canal and anus.

A change of cells to a form that does not normally occur in the tissue in which it is found.

A nutrient required to maintain health.

The moist, inner lining of some organs and body cavities (such as the nose, mouth, lungs, and stomach). Glands in the mucosa make mucus (a thick, slippery fluid). Also called mucous membrane.

A chemical compound (such as protein, fat, carbohydrate, vitamin, or mineral) contained in foods. These compounds are used by the body to function and grow.

A part of the body that performs a specific function. For example, the heart is an organ.

A type of anemia (low red blood cell count) caused by the body's inability to absorb vitamin B12.

A growth that protrudes from a mucous membrane.

A molecule made up of amino acids that are needed for the body to function properly. Proteins are the basis of body structures such as skin and hair and of substances such as enzymes, cytokines, and antibodies.

Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.

The outer lining of organs and body cavities of the abdomen and chest, including the stomach. Also called serous membrane.

The part of the digestive tract that is located between the stomach and the large intestine.

An organ that is part of the digestive system. The stomach helps digest food by mixing it with digestive juices and churning it into a thin liquid.

Cancer that forms in tissues lining the stomach. Also called gastric cancer.

The hollow tube inside the neck that starts behind the nose and ends at the top of the trachea (windpipe) and esophagus (the tube that goes to the stomach). The throat is about 5 inches long, depending on body size. Also called the pharynx.

A group or layer of cells that work together to perform a specific function.

A key nutrient that the body needs in small amounts to grow and stay strong. Examples are vitamins A, C, and E.