The prevention of colorectal cancer is the focus of new colorectal cancer screening guidelines issued this week by the American Cancer Society, in collaboration with the US Multi-Society Task Force on Colorectal Cancer and the American College of Radiology.
The new recommendations add two new screening methods to the list of screening options, and are more specific than in the past about the differences between the different types of available screening tests. The guidelines note that some tests, which are typically more invasive, allowf or the prevention of cancer because they are able to detect both early cancer and potentially pre-cancerous growths, called polyps. The polyps can then be removed before cancer develops. Other tests detect primarily colorectal cancers, and are less likely to detect colorectal polyps.
The guidelines indicate that doctors should encourage patients to use a screening test that is able to detect both polyps and cancer, provided that these tests are available and their patients are willing to have them done. According to the American Cancer Society, it is the first time the screening guidelines have expressed such a preference for one specific type of test over another.
Men and women at average risk for colorectal cancer should begin screening with one of the seven recommended options at age 50. Men and women who have certain risk factors, such as a family history of colorectal polyps or cancer, need to talk with their doctor about getting screened at a younger age.
The screening options are as follows:
Tests that Detect Both Cancer and Potentially Pre-Cancerous Polyps
- Colonoscopy every 10 years; OR
- Flexible sigmoidoscopy every 5 years; OR
- Double-contrast barium enema every 5 years; OR
- CT colonography (virtual colonoscopy) every 5 years.
- Guaiac-based fecal occult blood testing (gFOBT) every year; OR
- Fecal immunochemical test (FIT) every year; OR
- Stool DNA test (unclear how often this is needed).
If any of the stool tests show an abnormal result, follow-up with colonoscopy is needed. Some pre-cancerous polyps may be found by the stool tests; however, they are much less likely to find polyps than the other four screening options.
While the new guidelines state a preference for certain types of tests over others, the American Cancer Society emphasizes that getting tested -- with any of the approved methods -- is still what counts.
For more information on the new guidelines, visit the American Cancer Society at: www.cancer.org.
Source: Levin et al. Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: A joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology. Published online March 5, 2008. CA Cancer J Clin. 2008;58 and American Cancer Society, In The News report, www.cancer.org.