Colorectal Cancer Screening

Colorectal cancer screening means looking for the presence of cancer or pre-cancer in someone who does not show any signs or symptoms of the disease.

Most colorectal cancers begin as polyps (growths) in the lining of the large intestine. Over time, these polyps grow in size and number, increasing the risk that the polyps will become cancerous. Identifying polyps and removing them early reduces the risk of developing colorectal cancer. Screening can also identify colorectal cancer at an earlier stage when it is most treatable and curable.

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Did You Know?

Following colorectal cancer screening guidelines can reduce the incidence (number of newly diagnosed cases) of the disease. 

How Do I Know if I Am at High Risk for Colorectal Cancer?

You may be at a higher risk of developing colorectal cancer if you have:

  • Signs or symptoms of colorectal cancer

  • Had colorectal cancer or polyps before

  • A family history of colorectal cancer in a parent, sibling, or child (first-degree relative)

  • An inflammatory bowel disease such as Crohn’s disease or ulcerative colitis

  • An inherited cancer syndrome such as Lynch syndrome or familial adenomatous polyposis (FAP)

Colorectal cancer screening - summary of recommendations

When Should I Get Screened for Colorectal Cancer?

This video from the Canadian Cancer Society explains how to perform the FIT test.

The Canadian Cancer Society recommends that average risk adults aged 50 – 74 years have a stool test (FIT) every 2 years.

In the case of a positive stool test, follow-up should be done with a flexible sigmoidoscopy or colonoscopy.

Overview of most common colorectal cancer screening tests

  • Fecal Immunochemical Test (FIT or iFOBT): A test in which a stool sample is collected and returned to the doctor or lab to examine for small amounts of blood in the stool.

  • Colonoscopy: A thin, flexible, lit tube with a small video camera located at its end is inserted through the anus in order to view the inside of the entire colon and rectum for polyps and cancers.

  • Flexible Sigmoidoscopy: A thin, flexible, lit tube with a small video camera located at its end is inserted through the anus in order to view the inside of the lower part of the colon and rectum (usually around the lower two feet) for polyps and cancer-related growths.

Less common screening tests that may be available at select hospitals and clinics

  • CT Colonography (Virtual Colonoscopy): A less invasive test using special x-ray equipment to produce pictures of the colon and rectum. A screening alternative for individuals at higher risk of complications with standard colonoscopy, such as elderly patients.

If you are at a higher risk of developing colorectal cancer, you will likely participate in more frequent screening and begin at an earlier age. Be sure to discuss your personal risk factors with your doctor to develop an appropriate screening plan.

How Do I Get Screened for Colorectal Cancer?

In Canada, most provinces and territories have colorectal cancer screening programs available for average-risk adults aged 50-74.

Nunavut

No organized screening program – talk to your doctor about how you can get screened.

Learn More About Screening in Canada:

The following document outlines the colorectal cancer screening guidelines across Canada, including provincial and territorial programs, recommended screening methods, intervals, and protocols for average individuals and those with increased risks. It highlights the role of national organizations in promoting high-quality cancer screening services and provides detailed guidelines to improve participation and early detection efforts.