Colorectal Screening Options
Several different screening tests can be used to find polyps or colorectal cancer. Each can be used alone. Sometimes they are used in combination with each other. The U.S. Preventive Services Task Force (USPSTF) recommends colorectal cancer screening for men and women aged 50–75 using high-sensitivity fecal occult blood testing (FOBT), sigmoidoscopy, or colonoscopy. Talk to your doctor about which test or tests are right for you. 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.
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 to the doctor or a lab, where stool samples are checked for 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 five years. When done in combination with a High-Sensitivity FOBT, the FOBT should be done every three 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.
How Often: Every 10 years.
Colonoscopy also is used as a follow-up test if anything unusual is found during one of the other screening tests.
Other Screening Tests in Use or Being Studied
Although these tests are not recommended by the USPSTF, 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. The images are displayed on the computer screen.
Stool DNA Test
You collect an entire bowel movement and send it to a lab to be checked for cancer cells