Cancers of the gastrointestinal system can be especially hard to treat because they prevent the patient from taking in the nutrients they need to stay healthy.
Every year, many Americans die of cancer of the colon and rectum. About half of all cases of cancer of the colon can be cured by surgery, and early detection can greatly improve this percentage. A simple test for occult (not visible to the naked eye) blood in the stool can help to diagnose colon cancer. Everyone who is older than 50 years of age or who has chronic digestive problems should have screening tests for colon cancer regularly. Cure is twice as likely if the disease is discovered before symptoms occur. Periodic screening with a flexible sigmoidoscope or colonoscope is also recommended for men and women older than 50 years of age and for men and women over age 40 who have a family history of colon cancer.
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Symptoms of cancer of the colon include a change in bowel movements, bleeding from the rectum, pencil-thin stools, and abdominal discomfort not eased by bowel movement. If colon cancer is suspected, the physician will probably perform a rectal exam to search for unusual growths. If further examination is necessary, the doctor may introduce a colonoscope (a lighted, tubelike instrument) into the colon through the anus. This instrument permits examination of the inside of the colon and can also be used to obtain a biopsy specimen.
Surgery is the usual treatment for cancer of the colon. If the cancer is near or in the rectum, the surgeon may remove all of the rectum and create an artificial rectum, or colostomy, in the lower abdominal wall. A colostomy is covered with a bag to collect waste material. Colostomy is not automatically done for any colon cancer. The type of operation performed is dictated by the size and location of the tumor.
Liver cancer usually is caused by the spread of cancer cells from another site in the body. However, cancer that originates in the liver can sometimes be traced to environmental carcinogens. It is known that anyone who has worked with vinyl chloride, a chemical used in plastics manufacturing, has a higher risk of this disease. It also appears that cirrhosis of the liver (a disease in which normal liver cells are replaced by fibrous tissue) may cause an individual to be more susceptible to liver cancer. People who are chronic carriers of the hepatitis B or C virus may be at higher risk of liver cancer as well.
Symptoms of liver cancer may resemble the signs of a peptic ulcer -- aching or burning pain in the upper abdomen, nausea, and vomiting. A swollen or hardened liver often indicates to the doctor the need for further investigation.
If this form of cancer is diagnosed early and is confined to the liver, it can be treated surgically, but most often the prognosis is not good.
The incidence of stomach cancer has decreased by 50 percent in the last 25 years. A change in diet may account for this. Stomach cancer is more common in men than in women and usually occurs between the ages of 50 and 70. The high-risk group includes those with a history of pernicious anemia or alcoholism and those who choose a diet rich in smoked, pickled, or salted foods.
The symptoms of stomach cancer are similar to those of a peptic ulcer (heartburn and abdominal discomfort), which makes diagnosis more difficult. It may not be until the disease is well advanced that the identifying symptoms of bloody stools or vomit appear. A special X-ray study may be obtained after the patient swallows barium (a contrast substance that coats the lining of the stomach), which allows irregularities in the stomach (such as the presence of a tumor) to show up on X-ray films. If a tumor is identified, a flexible, lighted, tubelike instrument called an endoscope may be inserted down the throat into the stomach to examine the tumor more closely and perhaps obtain a biopsy specimen.
Surgery is the most effective treatment of this disease, but only about 10 percent of victims survive more than five years after diagnosis. Surgery is most useful when the tumor has not begun to spread. It is sometimes necessary to remove all or part of the stomach. After such surgery, the patient will require a modified diet.
In the next section, we look at cancers that are specific to a women.
This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.