What to expect from colonoscopy and other screening tests.

What Are Screenings Like?

There are several tests that you can have to screen for colorectal cancer (CRC) or for precancerous polyps.

Screening means that your colon and rectum are being checked to see if there are any signs of cancer or of cellular changes that could lead to cancer. Screening is done as part of preventive care, and not because a patient is having symptoms. 

If you are having symptoms of colorectal cancer, then your test likely will be diagnostic (following up on symptoms to determine the cause) rather than screening.

Your doctor can help you decide which test is right for you. If you are considered to be at average risk for CRC, you will have more choices. For people who are considered to be at higher risk, colonoscopy may be the only appropriate screening test.

Colonoscopy is the only test that can not only look for cancer, polyps and other precancerous lesions. It also is the only test during which polyps can actually be removed, preventing them from possibly progressing to cancer.

Several of the available tests require a full bowel cleansing beforehand, which your doctor's office will explain to you and help you manage. 

If you do have a test other than colonoscopy, and there is a positive result (a suspicion of polyps or cancer), then you will need to have a colonoscopy to follow up and take a thorough look at your colon and rectum. Information about all of the screening options is found on the "Which Screening Is for Me?" page. 

On this page, we will talk about colonoscopy. 

ASGE has a helpful video if you are preparing to have your first colonoscopy.

About Colonosopy

Colonoscopy is considered the "gold standard" of CRC screening. Here we provide in-depth answers to common questions about the procedure. 

About Colonoscopy

  • Why is colonoscopy performed?

  • What preparation is required?

  • Can I take my regular medications?

  • Is colonoscopy painful?

  • What happens during a colonoscopy?

  • What happens if the colonoscopy shows something abnormal?

  • Why is polyp removal (polypectomy) performed if found during the colonoscopy?

  • What happens after a colonoscopy?

  • What are the possible complications or risks of colonoscopy?

  • What sort of things should concern me after the colonoscopy?

For questions about this Web site, contact info@asge.org. For questions specifically related to your health and getting screened for colorectal cancer, contact your doctor, or find a GI doctor in your area.

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The Patient Protection and Affordable Care Act

The Patient Protection and Affordable Care Act, passed in 2010, waives the coinsurance and deductible for many colon cancer screening tests, including colonoscopy, sigmoidoscopy and fecal occult blood testing (FOBT). Colonoscopy is a unique screening test because gastroenterologists are able to remove precancerous polyps during the screening procedure. Under Medicare billing rules, removal of any polyp reclassifies the screening colonoscopy as a therapeutic procedure, for which patients will receive a coinsurance bill. This is often unexpected by patients under the impression that deductible or coinsurance charges were waived.

There are efforts ongoing to correct this problem. ASGE, along with the American Cancer Society Cancer Action Network (ACS CAN), and the American Gastroenterological Association (AGA), are advocating that Congress fix this "cost-sharing" problem, which continues to cause confusion for patients and providers. The Removing Barriers to Colorectal Cancer Screening Act of 2012 introduced in March 2012 by Rep. Charlie Dent, R-PA, waives the coinsurance for a screening colonoscopy regardless of whether a polyp or lesion is found. Congressman Dent's bill applies the same rational policy to beneficiary coinsurance. The expectation is that this will eventually be corrected.

Private Insurance

In February 2013, the federal government issued an important clarification on preventive screening benefits under the Affordable Care Act. Patients with private insurance will no longer be liable for cost sharing when a pre-cancerous colon polyp is removed during screening colonoscopy. This ensures colorectal cancer screening is available to privately insured patients at no additional cost, as intended by the new healthcare law. Patients with Medicare coverage must still pay a coinsurance when a polyp is removed as a result of the screening colonoscopy.

Click here for the guidance language provided by the administration. Patients with private insurance should check with their individual providers to learn the details of their coverage and ask about the Affordable Care Act.

For questions about this Web site, contact info@asge.org. For questions specifically related to your health and getting screened for colorectal cancer, contact your doctor, or click here to find a doctor in your area.

Colorectal Cancer Screening Tests Covered by Medicare

In 2000, Medicare started paying for colonoscopy for people age 50 and older. Prior to 2000, Medicare only covered the exam for people at high risk or with symptoms. People on Medicare now have more choices for screening tests.

For people on Medicare, this is what is covered:

  • Stool blood test (FOBT or FIT) each year for those 50 and over
  • Flexible sigmoidoscopy (flex-sig) every four years for those 50 and over at average risk
  • Colonoscopy every two years for those at high risk
  • Colonoscopy once every 10 years for those 50 and over at average risk
  • Barium enema with air contrast instead if a doctor believes that it is as good as or better than flex-sig or colonoscopy
  • Virtual colonoscopy is not covered by Medicare as an initial screening test

Colonoscopy is the most commonly utilized screening test for colon cancer since it has a high yield of detecting precancerous polyps and is able to remove them.