Cancer screening tests look for cancer before you have any signs or symptoms.

With colorectal cancer screening, we can often find cancer early, before it has spread, and sometimes, even before it's cancer. When we find colorectal cancer early, we have more treatment options, treatments are more effective, and we have a better chance of curing your cancer.

At Carilion, we consider national guidelines and the collective expertise of our physician leaders for our screening recommendations. We suggest all adults with an average risk for colorectal cancer aged 45 to 75 get routine screenings.

If you're between 76 and 85, talk to your doctor about whether continuing screening is right for you. Screening should stop after age 85.

Most people think of a colonoscopy for colorectal cancer screening. We have a range of tests available that can screen you for colorectal cancer. Screening frequency—how often you get colorectal cancer screenings—depends on your chosen screening test and your results.

The USPSTF lists 6 colorectal cancer screening tests that can help find cancer early. There are 2 types: stool-based tests and visual screening tests. Your doctor can help you decide which one makes sense for you. 

You'll need a colonoscopy if a stool-based or visual screening test is abnormal.

These tests look for hidden blood or DNA changes in a stool sample. These aren’t proof of colorectal cancer, but they can be a sign of it.

Your primary care team can help determine which stool-based screening test is right for you and order the test if appropriate.

Stool-based tests are convenient, but you have to do these tests more often, and they have a higher risk of a false positive (the screening test says you need further testing, but you don’t have cancer). For some people, the uncertainty can cause anxiety.

For these tests, your care team will give you a kit to help you collect your stool samples. Follow the instructions in the kit. You'll either mail the samples in the envelope or box provided or return them to your doctor’s office for lab testing.

You will get your results in 1 – 2 weeks. Your doctor will review the results and whether you need follow-up testing with a colonoscopy.

We recommend 2 types of noninvasive colon cancer screening stool-based tests:

Fecal immunochemical test every year

Called FIT for short, this test uses 1 stool sample. It looks for hidden blood in the stool from the lower intestines.

It’s less likely to pick up blood from other parts of your digestive tract. So, it’s less likely to cause false positives.

sDNA-FIT (Cologuard) every 1 – 3 years

Stool DNA (sDNA) tests find cells in your stool with DNA changes caused by colorectal cancer and polyp cells. An SDNA-FIT test checks your stool for both DNA changes and hidden blood.

For this testing, you need to collect a full bowel movement. Screening frequency is every 3 years. False positives are more likely when screening every 1 or 2 years.

Visual screening uses special imaging tools to look for cancer inside your colon and rectum.

There are 3 types of visual screenings:

Colonoscopy every 10 years

A colonoscopy is a procedure done in the hospital or ambulatory endoscopy center. You'll be under general anesthesia or sedation. So, someone will need to drive you home from the procedure. You’ll go home that day.

Before this procedure, you'll need to empty your bowels completely by following specific “bowel prep” instructions. 

During a colonoscopy, we'll insert a tiny video camera through your anus to look for polyps and cancer inside your rectum and colon. A colonoscopy can also prevent cancer because we can remove suspicious polyps and anything else we want to check for cancer. 

Potential risks, while rare, include bleeding and bowel perforation or other injury caused by the camera.

CT colonography every 5 years

This screening test combines X-rays and computed tomography (CT) scans to make a 3D image of the colon and rectum. This can help us find abnormal areas, such as cancer or polyps. 

We also call this a virtual colonoscopy.

For this test, you also need to empty your bowels completely. However, you're not under sedation. A CT colonography is a noninvasive colon cancer screening option. We don't insert tools into the bowel, so we can’t remove polyps. If anything looks suspicious, we’ll need to do a colonoscopy to take a sample.