Stomach Cancer
Stomach cancer, also called gastric cancer, is a disease in which the cells in the stomach divide without control or order and take on an abnormal appearance. These cancerous cells often spread to nearby organs and to other parts of the body.
How Does Stomach Cancer Develop?
The stomach is the sac-like organ located in the upper abdomen, under the ribs, which plays a role in the digestion of food. It connects the esophagus (e-SOF-a-gus), the tube that carries swallowed food, with the small intestine, which absorbs the nutrients needed by the body. When food enters the stomach, the muscles in its wall create a rippling motion that mixes and mashes it. The glands in the lining of the stomach release juices that help to digest the mixture. After a few hours, the food becomes a liquid and moves into the small intestine, which makes it easier for the intestine to continue the process of digestion and absorb the substances that the body needs for energy.
Stomach cancer begins when some of its cells take on an abnormal appearance and begin to divide without control or order. If left untreated, these cancer cells can grow through the stomach wall, and they can spread to nearby organs or to nearby lymph nodes*. Through the lymphatic system, the cancer cells can spread to distant areas of the body, including the lungs and the ovaries.
About 95 percent of all stomach cancers are adenocarcinomas, which start in the glandular cells of the stomach. Other types of stomach cancer include malignant transformation of the immune tissue of the stomach wall, which causes lymphoma of the stomach wall; cancer affecting the hormone-producing cells in the stomach that causes a condition called carcinoid tumor; and gastrointestinal stromal tumors, a rare form of stomach cancer that affects nervous system tissue within the stomach.
Who Gets Stomach Cancer and Why?
Each year, about 24,000 people in the United States learn that they have cancer of the stomach. Like most other forms of cancer, stomach cancer occurs most frequently in older people, usually 55 years of age or older. Fortunately, for reasons that scientists cannot fully explain, the number of people who get this disease dropped steadily between the 1940s and the carly 2000s.
Stomach cancer is much more common in other countries, especially Japan, Chile, and Iceland. Researchers think the reason may be that people in these countries eat many foods that are preserved by drying, smoking, salting, or pickling. Eating foods preserved in this way may raise someone's risk for developing stomach cancer. People who smoke cigarettes may also be at higher risk of developing stomach cancer.
What Happens When People Have Stomach Cancer?
Symptoms:
At first, stomach cancer does not cause any symptoms. And when it eventually causes symptoms, they often are mistaken for less serious stomach problems, such as indigestion, heartburn, or a virus. Therefore, it is hard to find stomach cancer early, which makes it more difficult to treat. Possible symptoms include:
* Discomfort or pain in the abdomen
* Nausea and vomiting after meals
* Bloating of the stomach after meals
* Anemia
* Weakness, fatigue, or weight loss
* Vomiting blood or passing black, tar-like stools
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