Stomach cancer (also called gastric cancer) is an abnormal and unregulated growth of the cells that make up the stomach. The stomach is a pouch that holds and stores food after eating, and helps in the process of digestion.

When you chew and swallow food, it travels from your mouth down a muscular tube called the esophagus. The esophagus delivers food to your stomach. The stomach is made up of a variety of cells, including some that produce substances that aid in digestion, such as acid and enzymes. Food from the stomach enters the duodenum, the first part of the small intestine, where digestion continues.

The Stomach

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Under certain conditions, stomach cells undergo changes that result in uncontrolled growth, and these cancer cells grow more rapidly than normal stomach cells. Cancer cells also lack the ability to organize themselves in a normal way and have the capability to invade other normal tissue.

If stomach cancer is caught very early, it may have only affected the lining of the stomach, called the mucosa. The longer cancer is allowed to grow, the more likely it is that cancer cells will invade other layers of the stomach. The tumor may then extend directly beyond the stomach, invading other surrounding organs and tissues, or travel through the bloodstream to invade distant organs and tissues (such as the liver, lungs, and/or bones). Tumor cells may also invade the vessels that carry lymph fluid or shed into the abdominal cavity, causing accumulation of abdominal fluid (called ascites).

Who Is Affected

It is estimated that 21,130 men and women (12,820 men and 8,310 women) will be diagnosed with cancer of the stomach in 2009. About 10,620 men and women will die of cancer of the stomach in 2009.

Stomach cancer is the 11th most common type of cancer diagnosed, and the 14th most likely to cause death. It is much more common among minority populations within the United States, ranking between the 4th and 6th most common cause of cancer death among minorities. Worldwide, it’s even more common. Deaths due to gastric cancer has decreased to 20% of that seen in 1930s in the United States, although it remains the the number two cause of cancer death (second only to lung cancer) worldwide.


Stomach cancer can cause serious, life-threatening bleeding. Heavy bleeding can cause ]]>anemia]]> , which is a lack of red blood cells and a decrease in the blood's ability to carry oxygen to your body's cells. Anemia can make you feel very weak and tired. Heavy bleeding can also cause heart complications, such as shortness of breath or palpitations (rapid heart rate), and brain complications, such as fatigue or lethargy.

Stomach cancer can interfere with your body’s ability to digest and therefore utilize nutrition from the food you eat, resulting in weight loss.

Over time, untreated stomach cancer will invade surrounding tissues or travel to neighboring lymph nodes, the lining of the abdominal wall (the peritoneum), the lungs, or the liver. When cancer spreads to the peritoneum, you may develop ascites, a collection of fluid in your abdomen. When cancer spreads to your liver, you may become ]]>jaundiced]]> (develop yellowish discoloration of your eyes and skin) or experience pain in the right upper abdomen. When cancer spreads to your lungs, you may become short of breath and develop a cough and wheezing.