Colorectal cancer screening options

Legacy Cancer Institute recommends colonoscopy, because it is the only screening test that can actually prevent cancer. During the colonoscopy, the doctor finds and removes any polyps, which can turn into cancer later.

If the thought of a colonoscopy is enough to keep you from having one, talk with your health care provider about other options, such as a take-home stool test (FIT). 

More about screening options

  • Colonoscopy – A colonoscope, a long, slender, flexible tube with a lighted end, is inserted into the colon through the rectum. This allows the doctor to look at the entire colon and to snip away polyps or anything that looks suspicious. Colonoscopy is the most accurate and complete of the screening test options. During the colonoscopy, you are given mild sedatives - most people sleep through the whole thing.
  • Flexible sigmoidoscopy – A sigmoidoscope, a slender, flexible tube with a lighted end, is inserted into the colon through the rectum. It allows the doctor to look for blood and/or polyps in the lower portion of the colon. Polyps can be removed, and any suspicious tissue can be snipped for biopsy.
  • Double contrast barium enema – A chalky liquid and air are pumped into the colon through the rectum, which makes the colon expand and allows clear X-rays to be taken.
  • CT colonography (computed tomographic colonography, also know as "virtual" colonoscopy) – Air is pumped into the colon through the rectum and a special CT scan of the expanded colon is taken. This is a new test, still being studied for effectiveness.
  • FIT, a take-home stool test – Most people find these tests easier than the ones described above, because they are not invasive and can be done at home. However, they cannot prevent cancer, like a colonoscopy. They are also not as accurate, so cancer could be missed. And, if you get a positive result, you’ll likely have to have a colonoscopy anyway.