The stomach is part of the digestive system and connects the esophagus to the small intestine. Once food enters the stomach the muscles in the stomach help to mix and mash the food using a motion called peristalsis.
Stomach cancer can develop in any part of the stomach and can spread throughout the stomach and to other organs such as the small intestines, lymph nodes, liver, pancreas and colon.
No one knows the exact reason why a person gets stomach cancer. Researchers have learned that there are certain risk factors associated with the development of stomach cancer. Those over the age of 55 years are more likely to get stomach cancer. Men are affected twice as often as women and African Americans are affected more commonly than Caucasians.
Stomach cancer is more common in some parts of the world such as Japan, Korea, parts of Eastern Europe and Latin America. Some studies do suggest that a type of bacteria known as Helicobacter pylori, which can cause inflammation and ulcers in the stomach, can be an important risk factor for developing gastric cancer.
Studies show that people who have had stomach surgery or have a condition such as pernicious anemia, or gastric atrophy (which result in lower than normal production of digestive juices) can be associated with an increased risk of developing gastric cancer.
There is also some evidence that smoking increases the risk of developing gastric cancer.
Patients may not have any symptoms in the early stages and often the diagnosis is made after the cancer has spread. The most common symptoms include:
In addition to taking a complete history and performing a physical exam, your doctor may do one or more of the following tests:
Upper GI series- The patient is asked to drink a barium solution. Subsequently x-rays of the stomach are taken. The barium outlines the inside of the stomach helping to reveal any abnormal areas that may be involved with cancer. This test is used less often than it used to be, and patients now often undergo endoscopy (see below) first.
Endoscopy- A lighted, flexible tube with a camera, called an endoscope, is inserted through the mouth into the esophagus and then into the stomach. Sedation is given prior to insertion of the endoscope. If an abnormal area is found, biopsies (tissue samples) can be taken and examined under a microscope to look for cancer cells.
If cancer is found, the doctor may schedule additional staging tests to determine if the cancer has spread. A CT scan may be used to determine if cancer has spread to the liver, pancreas, lungs or other organs near the stomach.
Staging of gastric cancer may also be performed by using endoscopic ultrasound. Endoscopic ultrasound can help to determine the depth of spread of the tumor into the wall of the stomach and involvement of adjacent structures as well as assess for any enlarged lymph nodes that may be invaded with cancer cells.
Treatment plans may vary depending on the size, location, extent of tumor and the patient's overall health. Treatments include surgery, chemotherapy and /or radiation therapy.
Surgery is the most common treatment. The surgeon can remove part of the stomach (gastrectomy) or the entire stomach. Lymph nodes near the tumor are generally removed during surgery so that they can be checked for cancer cells.
Researchers are exploring the use of chemotherapy before surgery to help shrink the tumor and after surgery to help kill residual tumor cells. Chemotherapy is given in cycles with intervals of several weeks depending on the drugs used.
Radiation therapy is the use of high-energy rays to damage cancer cells and stop them from growing. Radiation destroys the cancer cells only in the treated area.
Doctors are looking at the combination of surgery, chemotherapy and radiation therapy to see what combination would have the most beneficial effect.
Manoop S. Bhutani, MD, FACG, FACP, and Radha Tamerisa, MD, University of Texas Medical Branch, Galveston, TX – Published June 2004. Updated November 2008.