Hereditary Colon Cancer

What can be done to prevent colorectal cancer in my family?

Knowing the early warning signs of colon cancer is important. These signs can include rectal bleeding, crampy abdominal pain or discomfort, a persistent change in your usual bowel habits (constipation or diarrhea), or unexplained weight loss. However, often there are no obvious symptoms. For this reason, people who are considered to have an increased risk of colon cancer are advised to have colon screening. Screening usually starts in the mid-20's, but this varies for each family.

The purpose of screening is to identify cancer at the earliest possible stage, when it is most successfully treated. Screening can also prevent cancer by identifying and removing suspicious polyps in the colon. Polyps are small mushroom- shaped growths that are benign (noncancerous). These polyps can change to cancer more quickly than polyps in the general population.

The best available test is called a colonoscopy. Although uncomfortable, a colonoscopy allows a specialized doctor to examine the entire colon, from the rectum all the way to where it attaches to the small bowel. This test will let the doctor see any polyps. At the time of colonoscopy, most polyps can be biopsied or removed on the spot. Although not everyone with hereditary colon cancer will develop polyps, a biopsy can also identify changes in the lining of the colon that might be precancerous. A biopsy is a small sample of polyp or colon lining that is removed and examined under the microscope.

Although a colonoscopy is recommended for the early detection and prevention of cancer, other tests can be done:

Flexible sigmoidoscopy: This is a "shorter version" of a colonoscopy, done with a flexible tube that is passed through the anus into the colon. This test can often be carried out in the doctor's office and bowel preparation is required prior to the test. Sedation is not required.

Barium enema: This is an x-ray procedure. First, the colon is filled with barium (a thick, chalky fluid). The barium allows the bowel wall to be seen more clearly on x-ray film. The colon must be emptied before the x-ray. One major drawback of this test is that polyps cannot be biopsied or removed. Also, small polyps may be missed if the colon is not completely emptied.