FROM THE EDITORS

Screening can prevent colon cancer

Amindra Aurora, M.D.
Associate Medical Editor, Mayo Clinic Health Letter

One of the saddest diagnoses that I see as a gastroenterologist is that of colon cancer. The reason it is sad is because of all the common cancers, only colon cancer is easily preventable. It really is true that an ounce of prevention can pay dividends in the long run. Colon cancer accounts for about 6 percent of all cancers. But colon cancer screening — unlike screening for breast cancer, lung cancer, prostate cancer and others — is performed to prevent cancers, not just to find them.

What I mean by this is that the common screening tests available for most cancers pick up cancers as they occur. However, a colonoscopy picks up not only cancers, but also polyps that may eventually turn into cancers. It really is now clear that if polyps are removed during a colonoscopy, the risk of colon cancer falls dramatically over time. This makes sense, because most colon cancers develop from polyps. When you can remove these polyps by snipping them off, you remove the risk that the polyps will become cancer.

There are many ways to screen for colon cancers, but if any of the tests come back positive, a colonoscopy needs to be done. You may have heard that this can be an unpleasant test. Actually, most people say the preparation is more difficult than the test itself.

So what is involved? You need to cleanse the colon so that your doctor is able to see the inner colon lining. To do this, you have to drink a colon-cleansing solution, usually the day before the test. On the plus side, the solutions have become more palatable and the volume you need to drink has decreased. You may find it helpful to go on a liquid diet a day or two before starting the colon-cleansing preparation, as it is much easier to pass liquids than solids.

When you come in for the colonoscopy, you will be given a mild sedative to help you relax. Then a narrow scope with a camera at the end is inserted in your rectum and the screening test begins. If any polyps are seen, they can be safely removed in just about all cases right there and then. A colonoscopy typically takes less than 20 to 30 minutes and is very safe.

So, now that you know this cancer is easily preventable, what's stopping you? In reality, we now have the ability to make colon cancer a disease of the past.