Colon cancer and rectal cancer can be prevented. Colorectal cancer screening can also detect cancer early — when it is most curable.

We’re doing our best to remove any and all barriers to colorectal cancer screenings (here’s how you can help).

All adults (men AND women) over the age of 45 are at risk for colorectal cancer and should be screened for adenomatous polyps and cancer.

People with higher risk (possibly because of another condition or family history) should work with a doctor to develop a more individualized screening plan. Visit our Resource Library’s Screening Resources to learn more.

Facing a cancer diagnosis is a lot scarier than screening. Ask Amanda:

Learn more:  Resources to locate free or low-cost screening.

Colorectal Cancer Screening Tests

Test Name Finds Polyps? Finds Cancer? Requires Prep to Clean Colon? Requires Handling Stool? Polyps Removed During Test? Abnormal Areas Biopsied? Entire Colon Viewed? Other
Tests approved by the USPSTF and guaranteed covered by insurers
Flexible Sigmoidoscopy Yes Yes Yes No Yes Yes No Can be done alone every 5 years or in combination with FIT or gFOBT
Colonoscopy Yes Yes Yes No Yes Yes Yes
HemeSensa Fecal Occult Blood Test (gFOBT) Not Generally Yes No Yes No No N/A Requires follow-up colonoscopy if positive
CT Colonography (virtual colonoscopy) Yes Yes Yes No No No Yes Involves pumping air into colon to inflate
Stool DNA Test (Cologuard®) Yes Yes No Yes No No Yes Also determines genetic mutations that can indicate cancer
Fecal Immunochemical Test (FIT) No Yes No Yes No No N/A Requires follow-up colonoscopy if positive
Tests not approved by the USPSTF so may not be covered by insurers
PillCam COLON Yes Yes Yes No No No N/A Approved for use in patients following an incomplete colonoscopy or who cannot receive a colonoscopy
Blood-based Septin9 methylated DNA test (Epi proColon) No Yes No No No No N/A A blood test that can detect colorectal cancer. Approved for patients over 50 who avoid or are unable to undergo colonoscopy, FIT or gFOBT testing.

Read more about the USPSTF guidelines.


The entire colon must be cleaned out in order to perform a colonoscopy.

A doctor then uses a colonoscope (longer than a sigmoidoscope) to view the entire colon, including the rectum, and remove any polyps.

This is often considered the “gold standard” for colon screening as it can identify polyps and remove them in the same procedure.

CT Colonography (Virtual Colonoscopy)

CT colonography is a non-invasive, advanced CT scan of the colon and rectum that produces two and three-dimensional images of the colon and rectum.

The doctor then looks for polyps or cancer within the images.

The entire colon must be cleaned out for this procedure.

Air is pumped into the colon and the CT scan is taken. Your doctor won’t be able to see or remove polyps smaller than 5mm through this method.

But, if abnormalities are found, your doctor will talk to you about the appropriate diagnostic procedure moving forward.

Fecal Immunochemical Test (FIT)

The FIT test works like the gFOBT test, however unlike the gFOBT, there are no drug or dietary restrictions.

This test is also better at detecting blood than the gFOBT.

Fecal Occult Blood Test (GFOBT)

The gFOBT test is an in-home test used to detect blood that can’t be seen by the naked eye occurring in or on your bowel movements.

Place your stool on a test strip and then carefully package it up per the instructions.

When you get a test, you should also get instructions about how and where to send it.

Test results of either “positive” or “negative” determine if bleeding is occurring; however, they don’t indicate the cause.

To provide accurate samples, you should follow the indicated drug and dietary restrictions.

If your test result is positive, talk to your doctor or clinic about getting a diagnostic colonoscopy to figure out the cause of the bleeding.

Flexible Sigmoidoscopy

Before the test, an enema is done to clean out the lower part of the colon and the rectum.

(Some doctors require that the entire colon must be cleaned out.)

A doctor then uses a sigmoidoscope to look at the sigmoid colon and the rectum, removing any visible polyps.

Less than half of the large intestine and all of the rectum can be seen with this method.

The flexible sigmoidoscopy should be done in combination with the GFOBT or FIT test, which test for blood in the stool.

Stool DNA Tests

Cologuard® is a stool DNA test that looks for abnormal sections of DNA in the stool in addition to blood (hemoglobin) in the stool.

A kit is provided, and the stool is mailed to a lab that looks for abnormal DNA.

This test has been approved by the FDA for average risk adults age 45 and older.

To learn more about screening for colon cancer, watch “Screening, Signs & Symptoms of Colon Cancer” by Medical Advisory Board member Dr. Paul Limburg of Mayo Clinic.

Screening Options for High-Risk Cases

If you or someone in your family has been diagnosed with a genetic syndrome (like Lynch syndrome) that increases the risk for colon or rectal cancer, it’s important to discuss the following colorectal cancer screening options with your doctor.

Lynch Syndrome

The American Society of Clinical Oncology recommends these general screening guidelines for those with Lynch syndrome:

  • Colonoscopy every one to two years, beginning between the ages of 20 to 25 (or five years younger than the earliest age at diagnosis in the family, whichever is sooner)
  • Periodic upper endoscopy screening (this procedure uses a thin, flexible tube with a light inserted into the body to examine a specific region) for stomach or intestinal cancer, especially if a family member has had one of these cancers
  • Yearly urine cytology to screen for urinary tract cancer

Additional Screenings for Women

  • Yearly pelvic examination
  • Pap test
  • Transvaginal ultrasound (a test where a small ultrasound probe is inserted for a pelvic examination in order to obtain better imaging of the uterus)
  • Endometrial biopsy (an examination on a sample of tissue from the inner lining of the uterus done as a part of a pelvic examination)
  • CA-125 blood test (a test to detect a protein found to be elevated in the blood of some women with ovarian cancer) beginning between the ages of 25 to 30

Rectal and colon cancer screening options may change over time as new technologies are developed and we learn more about Lynch syndrome. It’s important to talk with your doctor about appropriate screening tests and come up with the screening plan that works best for you.