Gastric cancer is cancer that starts in the stomach.

Several different types of cancer can occur in the stomach. The most common type is called adenocarcinoma, which starts from one of the common cell types found in the lining of the stomach. There are several types of adenocarcinoma. Because other types of gastric cancer occur much less frequently, this article focuses on adenocarcinoma of the stomach.

Adenocarcinoma of the stomach is a common cancer of the digestive tract worldwide, although it is relatively uncommon in the United States. It occurs most frequently in men over 40 years old. This form of gastric cancer is extremely common in Japan, Chile, and Iceland. The rate of most types of gastric adenocarcinoma in the United States has declined over the years. Experts think the decrease may be related to reduced intake of salted, cured, and smoked foods.

Diagnosis is often delayed bcause symptoms may not occur in the early stages of the disease, or because patients self-treat symptoms that may be common to other, less serious gastrointestinal disorders (bloating, gas, heartburn, and a sense of fullness).

Risk factors for gastric cancer are a family history of gastric cancer, Helicobacter pylori infection, blood type A, smoking, a history of pernicious anemia, a history of chronic atrophic gastritis, a condition of decreased gastric acid, and a prior history of an adenomatous gastric polyp.

• Abdominal pain
• Breath odor
• Difficulty swallowing, particularly difficulty that increases over time
• Excessive belching
• Excessive gas (flatus)
• General decline in health
• Loss of appetite
• Nausea and vomiting
• Premature abdominal fullness after meals
• Unintentional weight loss
• Vague abdominal fullness
• Vomiting blood
• Weakness or fatigue

The following tests can help diagnose gastic cancer:

• Complete blood count (CBC) to check for anemia
• Esophagogastroduodenoscopy (EGD) with biopsy
• Stool test to check for blood in the stools
• Upper GI series

Surgical removal of the stomach (gastrectomy) is the only curative treatment. Radiation therapy and chemotherapy may be beneficial. A recent study showed that for many patients, chemotherapy and radiation therapy given after surgery improve the chance of a cure.

For patients in whom surgery is not an option, chemotherapy or radiation can improve symptoms but may not cure the cancer. For some patients, a surgical bypass procedure may provide relief of symptoms.

The stress of illness may often be eased by joining a support group with members who share common experiences and problems. See cancer - support group and gastrointestinal disorders - support group.

The outlook varies widely. Tumors in the lower stomach are more often cured than those in the higher area -- gastric cardia or gastroesophageal junction. The depth to which the tumor invades the stomach wall and whether lymph nodes are involved influence the chances of cure.

In circumstances in which the tumor has spread outside of the stomach, cure is not possible and treatment is directed toward improvement of symptoms.

• Fluid build up in the belly area (ascites)
• Spread of cancer to other organs or tissues
• Weight loss

Call your health care provider if symptoms of gastric cancer develop.

Mass screening programs have been successful in detecting disease in the early stages in Japan, where the risk of gastic cancer is very high. The value of screening in the United States and other countries with lower rates of gastric cancer is not clear.

The following may help reduce your risk of gastic cancer:

• Don't smoke.
• Eat a healthy, balanced diet rich in fruits and vegetables.

Gunderson LL, Donohue JH, Alberts SR. Cancer of the Stomach. In: Abeloff MD, Armitage JO, Niederhuber JE, Kastan MB, McKena WG, eds. Clinical Oncology. 3rd ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2004:chap 79.