Screening means checking or testing for a disease in a group of people who don’t show any symptoms of the disease. Screening tests help find colorectal cancer before any symptoms develop. When colorectal cancer is found and treated early, the chances of successful treatment are better.
If you are 50 to 74 years old and not at high risk for colorectal cancer, have a stool test every 2 years. If you are 75 or older, talk to your doctor about whether a stool test is right for you.
There is convincing evidence that stool tests with the right follow-ups can lower the number of deaths from colorectal cancer.
A stool test checks for hidden (occult) blood in the stool. Cancerous tumours and other growths in the lining of the colon or rectum (such as polyps) have blood vessels on their surface that can release a small amount of blood into the stool. Stool tests help identify adenomas (adenomatous polyps) early, before they become cancerous.
There are 2 types of stool tests used to screen for colorectal cancer in Canada.
Find out more about stool tests.
A positive stool test result means that blood has been found in the stool. People who have a positive result will need to have follow-up tests. They include:
A negative stool test result means that blood has not been found in the stool. If you have a negative stool test result, you should have another stool test in 2 years.
See your doctor if you have blood in the stool, bleeding from the rectum or other signs and symptoms of colorectal cancer in between stool tests.
Most provinces have organized colorectal cancer screening programs with specific guidelines. Although the guidelines may be different in each province and territory, all guidelines include regular stool tests to help find colorectal cancer early.
Make sure to read the instructions included with your stool test. Depending on the type of test and your province, there might be medicine or food restrictions. And each program will have instructions on how to provide a sample and how to return the test.
Ask your doctor about how the program works where you live.
You can also call the Canadian Cancer Society’s Cancer Information Service toll-free at 1-888-939-3333 for information about colorectal cancer and screening programs.
Some people have a higher risk of colorectal cancer. People at higher risk may need to be tested more often and at an earlier age than people with average risk. You may be at higher risk if you have:
Talk to your doctor about your risk. If you are at higher risk, you may need a personal plan for testing. This may include:
To make the decisions that are right for you, ask your healthcare team questions about screening.