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Colon Cancer Genetic Testing - How Accurate Is the Test?

Although these blood tests are highly reliable, no test is 100% accurate. The test cannot tell you when or whether you will develop colon cancer. Testing negative for an inherited colon cancer gene does not mean you will never get colon cancer. It means your risk of colon cancer is about the same as that of the average person.

There are many different genetic mutations that can lead to FAP or HNPCC. Genetic testing does not find all of them. Because of this, a person may have a normal genetic test but still have an increased chance of having an inherited colon cancer.

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Who is at Risk?

For the great majority of people, the major factor that increases a person's risk for colorectal cancer (CRC) is increasing age. Risk increases dramatically after age 50 years; 90% of all CRCs are diagnosed after this age. The history of CRC in a first-degree relative, especially if before the age of 55 years, roughly doubles the risk. Other risk factors are weaker than age and family history. People with inflammatory bowel disease have a much higher risk of CRC. A small percentage (<5%) of CRCs...

Read the Who is at Risk? article > >

    This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http:// cancer .gov or call 1-800-4-CANCER.

    WebMD Medical Reference from Healthwise

    Last Updated: August 27, 2012
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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