Colorectal Cancer Screening Tests
Several screening tests can be used to find polyps or colorectal cancer.
Recommended Screening Tests
The U.S. Preventive Services Task Force recommends colorectal cancer screening for men and women aged 50–75 using high-sensitivity fecal occult blood testing (FOBT), sigmoidoscopy, or colonoscopy. (The decision to be screened after age 75 should be made on an individual basis. If you are older than 75, ask your doctor if you should be screened.)
Talk to your doctor [PDF-178KB] about which of the following tests are right for you.
High-Sensitivity FOBT (Stool Test)
There are two types of FOBT. One uses the chemical guaiac to detect blood. The other, a fecal immunochemical test (FIT), uses antibodies to detect blood in the stool. 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.
How often: Once a year.
For this test, the doctor puts a short, thin, flexible, lighted tube into your rectum. The doctor checks for polyps or cancer inside the rectum and lower third of the colon.
How often: Every 5 years with FOBT every 3 years.
This is similar to flexible sigmoidoscopy, except the doctor uses a longer, thin, flexible, lighted tube to check for polyps or cancer inside the rectum and the entire colon. During the test, the doctor can find and remove most polyps and some cancers. Colonoscopy also is used as a follow-up test if anything unusual is found during one of the other screening tests.
How often: Every 10 years.
Other Screening Tests in Use or Being Studied
Although these tests are not recommended by the U.S. Preventive Services Task Force, they are used in some settings and other groups may recommend them. Many insurance plans don’t cover these tests, and if anything unusual is found during the test, you likely will need a follow-up colonoscopy.
Double-Contrast Barium Enema
You receive an enema with a liquid called barium, followed by an air enema. The barium and air create an outline around your colon, allowing the doctor to see the outline of your colon on an X-ray.
Uses X-rays and computers to produce images of the entire colon, which are displayed on a computer screen.
Stool DNA Test
You collect an entire bowel movement and send it to a lab to be checked for cancer cells.
How Do I Know Which Screening Test Is Right for Me?
There is no single “best test” for any person. Each test has advantages and disadvantages. Talk to your doctor about the pros and cons of each test, and how often to be tested. Which test to use depends on—
- Your preferences.
- Your medical condition.
- The likelihood that you will get the test.
- The resources available for testing and follow-up.
- Screening Tests At-a-Glance brochure insert [PDF-204KB]
- Colon Cancer Screening Methods video (National Institutes of Health)
- Colonoscopy video (National Institutes of Health)
- Flexible Sigmoidoscopy (National Digestive Diseases Information Clearinghouse)
- Colonoscopy (National Digestive Diseases Information Clearinghouse)
- Virtual Colonoscopy (National Digestive Diseases Information Clearinghouse)
- Blog post: Why I Chose FIT—And You Can, Too!
- Personal Screening Stories