On average, colorectal cancer, which includes cancer of the large bowel (colon), and cancer of the rectum, claims the lives of 25 Canadians every day.
Despite the screening options available, many people have never been screened for the disease. Innovators in the medical space have now developed a simple blood test, called liquid biopsy, which for many folks is a more convenient option than undergoing traditional stool tests.
Let’s learn more about the colorectal cancer screening options available to you depending on your risks and preferences.
Colorectal cancer starts with changes in the cells of the colon and rectum. Changes can occur to these cells as a result of environmental or lifestyle factors, inflammatory conditions, genetic predisposition or even random chance. These changes may lead to the development of growths in the colon called polyps. Over time, some of these polyps may develop into cancer if they are not detected and removed at an early stage.
In Canada, colon cancer is the fourth most commonly diagnosed cancer, and the second and third leading cause of cancer deaths in men and women, respectively.
Fortunately, it’s possible to dramatically reduce deaths from colorectal cancer — through early detection and treatment. When caught early, nine out of 10 cases of colon cancer can be treated successfully.
The screening options your healthcare provider recommends, and the age at which you should start screening, will depend on your risk level for colorectal cancer, considering factors such as your family history, personal history and any symptoms you may be experiencing.
Higher than average risk
If you have a higher than average risk of developing colorectal cancer based on your personal medical or family history, your physician may recommend a referral for diagnostic screening with a colonoscopy or sigmoidoscopy (screening of only the lower half of the colon and rectum). This type of screening can find polyps at early stages and remove them before they have the opportunity to turn into cancer. However, this is an invasive procedure with some risks. If you’re unsure about your colorectal risk level, speak to your healthcare provider for the appropriate recommendation for you. The right age to start screening will also depend on your healthcare provider’s recommendation based on your risk factors.
Average risk
For those at average risk for colorectal cancer, there could be two options for regular screening. One is a stool-based, provincially-funded test called a fecal immunochemical test (FIT). If this test comes back positive, or if you are experiencing concerning symptoms, you may be referred for a colonoscopy as a second step. FIT tests are for individuals aged 50 to 74 and they are repeated every two years.
The second option is called liquid biopsy. This newer technology looks for signs of tumour DNA within your bloodstream. This type of screening isn’t covered by provincial health insurance plans. However, liquid biopsy has the advantage of being more convenient than a stool sample because it’s a simple blood test while being as sensitive as the FIT test.
The Canadian population has had access to the FIT test for many years and this test is highly sensitive, meaning that it does a good job of detecting colorectal cancer in those who have it. Despite the test’s widespread availability, fewer than 60 per cent of those eligible for screening have done their FIT test in the past two years.
There are many possible reasons for why so many people are not getting screened. Individuals may be embarrassed to talk to their healthcare provider about testing. If they don’t have a family history of colon cancer or are not experiencing any symptoms, they may believe they are not at risk – and therefore don’t need to test. Many Canadians also face systemic barriers to accessing adequate healthcare, including cancer screening.
“The best colorectal cancer screening test is one that gets completed,” says Corissa Androich, Genetic Counsellor and Senior Program Manager at TELUS Health. “The ultimate goal is to find ways to increase screening compliance, in turn potentially preventing colorectal cancer or detecting at earlier stages where it is easier to treat.”
A new type of colorectal cancer screening called liquid biopsy makes the process as easy as having a blood test. Liquid biopsy is a leading edge approach to screening for cancer that looks for biomarkers released into the bloodstream from cancer cells.
After discussing if this test is appropriate for you with your healthcare provider, a blood sample can be taken and sent to the laboratory for testing. Results are usually available in two weeks. Your healthcare provider will review them and refer you for additional follow-up tests (a colonoscopy), if needed.
The liquid biopsy test is not only easy and convenient, it’s as sensitive as the FIT test.
Liquid biopsy is currently available at our North Vancouver TELUS Health Care Centre to clients age 45 and older with a family physician at our clinic, or those who are part of our LifePlus membership program. The test costs $1,495 plus applicable taxes and is not covered by provincial public insurance plans, although you may be eligible for reimbursement through your extended health insurance or other employee benefits, such as a Health Spending Account (HSA) or a Wellbeing Account (WBA).*
To book an appointment, contact your clinical coordinator. Stay tuned as we work toward expanding this service to other clinics.
*We recommend reaching out to your extended health insurance provider to review your current coverage. Balances not covered through your insurance may be tax-deductible as a medical expense when filing your annual income taxes, depending on the services rendered.