The U.S. Preventive Services Task Force (USPSTF) recommends that adults age 45 to 75 be screened for colorectal cancer. The decision to be screened between ages 76 and 85 should be made on an individual basis. If you are older than 75, talk to your doctor about screening. 

 

People at an increased risk of getting colorectal cancer should talk to their doctor about when to begin screening, which test is right for them, and how often to get tested.

 

Several screening tests can be used to find polyps or colorectal cancer. The Task Force outlines the following colorectal cancer screening strategies. It is important to know that if your test result is positive or abnormal on some screening tests (stool tests, flexible sigmoidoscopy, and CT colonography), a colonoscopy test is needed to complete the screening process. Talk to your doctor about which test is right for you.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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CDC recommended screening tests and intervals

 

Stool Tests

 

• The guaiac-based fecal occult blood test (gFOBT) uses the chemical guaiac to detect blood in the stool. It is done once a year. For this test, you receive a test kit from your health care provider. At home, you use a stick or brush to obtain a small amount of stool. You return the test kit to the doctor or a lab, where the stool samples are checked for the presence of blood.

• The fecal immunochemical test (FIT) uses antibodies to detect blood in the stool. It is also done once a year in the same way as a gFOBT.

• The FIT-DNA test (Cologuard) combines the FIT with a test that detects altered DNA in the stool. For this test, you collect an entire bowel movement and send it to a lab, where it is checked for altered DNA and for the presence of blood. It is done once every three years.

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Colonoscopy

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• Colonoscopy, where physicians use a flexible, lighted tube (colonoscope) to look at the interior walls of the rectum and the entire colon, should be done every 10 years (for people who are not at increased risk of colorectal cancer). During this procedure, samples of tissue may be collected for closer examination, or polyps may be removed. Colonoscopies can be used as screening tests or as follow-up diagnostic tools when the results of another screening test are positive. Colonoscopy also is used as a diagnostic test when a person has symptoms, and it can be used as a follow-up test when the results of another colorectal cancer screening test are unclear or abnormal.

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Less Common Tests

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• Computed tomography (CT) colonography, also called a virtual colonoscopy, uses X-rays and computers to produce images of the entire colon, which are displayed on a computer screen for the doctor to analyze. This test is done every 5 years. 

• Flexible sigmoidoscopy, where physicians use a flexible, lighted tube (sigmoidoscope) to look at the interior walls of the rectum and part of the colon, should be done every five years with FOBT every three years.

                                                         Source: CDC.gov