New Colorectal Cancer Screening Guidelines Focus on Prevention

March is national colon cancer awareness month so it is fitting a consortium of cancer groups have published new guidelines for screening colorectal cancer. These guidelines focus on prevention and early detection.

The guidelines were issued by the American Cancer Society Colorectal Cancer Advisory Group, the U.S. Multi-Society Task Force, and the American College of Radiology Colon Cancer Committee.

These recommendations add two new screening tests: stool DNA and CT colonography, also known as “virtual colonoscopy” to the list of options. The stool DNA test is a relatively new screening method. It tests the stool for certain changes in DNA known to be related to colon cancer. More research is needed to determine how often the test needs to be done to have the best chance of finding cancer.’ CT colonography involves taking CT images of the colon while it is filled with air to look for polyps or cancerous growths.

The new guidelines stress that doctors should encourage patients to have tests that detect both polyps and cancer. This is the first time the guidelines have stated a preference for one kind of test over another.

The new guidelines are specific about the differences between various types of tests.” They state that some tests, which tend to be more invasive, offer the best chance of preventing cancer because they find pre-cancerous polyps, which can be removed before cancer develops.’ Other tests are less likely to find pre-cancerous growths, but can still detect most cancers.

“I like these new guidelines because they urge doctors to encourage patients to get the appropriate tests that find both polyps and cancer,” said colorectal surgeon Martin Luchtefeld, M.D., medical director of digestive diseases, Spectrum Health. “The previous recommendation just listed options and physicians and patients were left to determine what works best for them. That has changed with these recommendations.”

Luchtefeld said these guidelines should help doctors and patients make better decisions about screening. “Research has shown that certain tests are more likely to prevent and detect colon cancer. Another step made with the guidelines is that colorectal cancer prevention should be the primary goal of screening.”

Luchtefeld stresses that colon cancer is one of the most preventable cancers. It also is one of the most curable when found early. “Removing a polyp is like removing a mole on the skin before it might become cancerous. Both are medically simple, but people have to be motivated to follow through. If everyone would follow screening guidelines, we would see a tremendous drop in the number of colorectal cancer deaths.”

Colorectal cancer, also called colon cancer, is the third most common cancer diagnosed among Americans and the second leading cause of cancer death in the U.S. The American Cancer Society estimates it will cause about 49,960 deaths (24,260 men and 25,700 women) during 2008.

American Cancer Society recommendations for colorectal cancer early detection

People at average risk

The American Cancer Society believes that preventing colorectal cancer (and not just finding it early) should be the primary reason for getting tested. Finding and removing polyps keeps some people from getting colorectal cancer. Tests that have the best chance of finding both polyps and cancer are preferred. These are general guidelines. For specific questions about these tests, talk to your physician.

Beginning at age 50, both men and women at average risk for developing colorectal cancer should use one of the screening tests below:

Tests that find polyps and cancer

  • flexible sigmoidoscopy every 5 years’
  • colonoscopy every 10 years’
  • double contrast barium enema every 5 years
  • CT colonography (virtual colonoscopy) every 5 years

Tests that mainly find cancer

  • fecal occult blood test (FOBT) every year
  • fecal immunochemical test (FIT) every year
  • stool DNA test (sDNA), interval uncertain

People at increased or high risk

If you are at an increased risk of colorectal cancer, you should begin colorectal cancer screening earlier and be screened more often. This is something you should discuss with your physician.

The following conditions place you at higher than average risk:

  • a personal history of colorectal cancer or adenomatous polyps’
  • a personal history of inflammatory bowel disease (ulcerative colitis or Crohns disease)’
  • a strong family history of colorectal cancer or polyps (see “Risk factors for colorectal cancer” above)’
  • a known family history of hereditary colorectal cancer syndromes such as familial adenomatous polyposis (FAP) or hereditary non-polyposis colon cancer (HNPCC).