GUAA :: Risk Review

The colon is part of the digestive tract, which absorbs water, processes food for energy and eliminates waste products. The colon, or large bowel, is the last section of this system and is approximately 5 feet long. The last six inches of the colon is considered the rectum.

Colon cancer is the third most common cancer in the United States and the number one cause of cancer death in non-smokers. (Lung cancer is the leading cause in smokers). The American Cancer Society estimates there will be 150,000 new cases diagnosed in the United States in 2005, with over a third (56,000) dying from the disease. We could cut the mortality number in half if everyone aged 50 or older were screened for colon cancer.

The majority of colon cancers begin as a benign polyp, which usually produces minimal to no symptoms. The goal in colon cancer screening is to find and remove these polyps before they transform into cancer, thus preventing cancer from developing at all, as it usually takes several years before a cancer develops in a polyp. Another goal with screening is to find any cancer already present at an early, more likely curable stage. Colon cancer detected early has a 5-year survival rate of 95%!

The American Cancer Society last month kicked off a humorous ad campaign stressing the importance of colon cancer testing. You may have recently seen their TV Ads. If we can increase the awareness of colon cancer, many more people at risk may go in for screening. Unfortunately, only half of the people over 50 are actually getting screened despite the fact that potentially fatal colon cancer is largely a preventable disease. The goal is to promote awareness and encourage screening for colon cancer, thus decreasing the incidence and mortality from this deadly disease.

By far, the most important risk factor for colon cancer is age. Over 90% of all colon cancer is diagnosed in people over the age of 50. If you are 50 or older, you are at risk for colon cancer, regardless of family history. Men and women are equally at risk. Other risk factors include: high dietary fat intake, obesity, diabetes, smoking, and heavy alcohol use.

Several screening tests are available. The fecal occult blood test (FOBT) looks for traces of blood in the stool as some polyps and cancers may bleed but the amount of bleeding may be too small to be seen by the naked eye. It is a simple, inexpensive, take-home test generally performed only once per year. Many studies have confirmed its value in detecting colon cancer.

The flexible sigmoidoscopy allows for direct visualization of the lower third of the colon, where 50% of the cancers are found. This may be done directly in your doctor’s office without sedation and typically only lasts 20 minutes. Polyps, if seen, may be removed at the same time.

Colonoscopy is the most accurate screening test, allowing for direct visualization of the entire colon. It generally is more comfortable than the flexible sigmoidoscopy, as sedation is generally given. The entire test is usually completed within one hour and again polyps may be removed, if found.

The double-contrast barium enema is a specialized X-ray of the colon. The sensitivity for detecting polyps is much lower than a colonoscopy and some polyps may be missed. Unfortunately, there is no option for biopsy if an abnormality is found, thus all abnormal findings require a follow-up colonoscopy.

The American Cancer Society recommends beginning at age 50; those at average risk should have one of the following:
   1. Fecal Occult Blood Testing (FOBT) every year
   2. Flexible sigmoidoscopy every 5 years
   3. Both #1 and #2
   4. Double Contrast Barium Enema (DCBE) every 5 years
   5. Colonoscopy every 10 years
You may need to be screened earlier or more often, if you have a family history of colon cancer or any of the risk factors mentioned above.

Colon cancer is largely a preventable disease. It is also frequently curable if found at an early stage. Earlier detection of colon cancer through proper screening can save lives. We need to stop colon cancer before it starts. It’s one cancer you can avoid by being pro-actively involved in your health care. Have you had your American Cancer Society recommended Colon Cancer Screening?