Bottom Line - The Importance of Colon Cancer Screening

Any cancer is hard to talk about, but colon cancer may be one of most uncomfortable to discuss.  So, many of us just avoid the topic altogether.

But even though colon cancer may not get as much recognition as some other types, it’s important to talk about because it is the second most common cancer killer in the United States. What’s even more staggering is that the majority of colon cancer cases could be prevented with screening tests but that many people don't know what screening options are available, or when they should talk with a doctor about them.

So, what is colon cancer screening and who should talk to his or her doctor about it? First, colon cancer is often used as shorthand for colorectal cancer, which is cancer that affects the large intestine and/or rectum. Screening can help find colon cancer in early stages, when it's more likely to be cured, and it can help prevent cancer by catching and removing precancerous growths, called polyps, before they turn into cancer. Men and women both are at risk for colon cancer, so everyone should be screened regularly for it, generally starting at age 50.

There are three common screening tests for colorectal cancer. Each looks for the presence of cancer or polyps. Talk with your doctor about which test may be best for you, and how often you should have it.

Colon Cancer Screening Tests

1. Colonoscopy: This test is completed every 10 years and is the most common colon cancer screening test. Your doctor will use a long and flexible light tube to check your entire colon for any polyps or cancer. If any polyps exist, they can be removed during the procedure. Removing precancerous polyps can prevent cancer. During a colonoscopy, you will be sedated, so you won’t feel anything. A colonoscopy is also used as a follow-up test if other screening tests find anything abnormal.

2. Stool Test (FOBT/FIT): This simple test, completed through a stool sample, should be done every year. You can complete the test in the privacy of your own home and submit the stool sample to a lab or your doctor’s office to test for the presence of blood. Blood in stool can be a sign of cancer.

3. Flexible Sigmoidoscopy: This should be completed every five years and is very similar to a colonoscopy except that it examines only the rectum and lower portion of the colon, rather than the entire colon. For this reason, sigmoidoscopy isn’t performed as frequently as colonoscopy. The sigmoidoscopy is often done without sedation.

Those at increased risk of colon cancer because they have family members with colon cancer, have had polyps before, or have a chronic inflammatory bowel disease may need to begin screening before age 50 and get it done more often.

Over 40 percent of people eligible for colon cancer screening either don't get tested or aren't up to date with testing. That's a huge number for such effective tests.  Take control and talk to a doctor to make sure you're getting the benefits of screening. It may not be the most comfortable conversation, but it's well worth it.

For more information about colon cancer screening, visit Siteman Cancer Center’s colorectal cancer webpage or 8 Ways to Prevent Colon Cancer, or call 1-800-600-3606 for a referral.

Written by: Jean Wang, MD, PhD, is an associate professor of medicine at Washington University School of Medicine in St. Louis. A gastroenterologist who screens for colorectal cancer at Siteman Cancer Center, she also works with patients to understand and reduce cancer risk before a diagnosis.

All opinions expressed here are those of their authors and/or contributors and not of their employer.
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