Skip to main content

The Question: At our last visit, my doctor handed me a kit to test for blood in my stool to screen for colorectal cancer. I recently turned 50, I'm a healthy male, I have no symptoms and nobody in my family has had this type of cancer. I'm not too keen on doing this test and it seems a little messy. Is it really necessary given that I feel fine?

The Answer: Your question reminds me of a conversation I had with a patient a few years ago. The 53-year-old man was relatively new to our practice and he had come in to get a prescription for blood pressure pills. I noticed that he had not been screened for colorectal cancer so I discussed options for testing with him.

Initially, he had a similar response to yours but after a full discussion of the benefits – and despite his discomfort – he took the kit with him. A few months later, I hadn't received his results so I checked in with him. He admitted that he wasn't comfortable doing the test so he opted out.

Later in the year, I saw him to discuss testing again, this time on his own initiative. One of his good friends had been diagnosed with colorectal cancer and it was very upsetting. Seeing his friend go through surgery as well as invasive testing and treatment motivated my patient to take the steps to get screened.

When I received his test result a couple of weeks later it was positive for blood in his stool. He then had a colonoscopy, which revealed several small polyps in his colon that were removed. There were no malignant cells, but polyps have the potential to turn into cancer over time. Therefore, removing the polyps early helps to reduce a patient's risk of colorectal cancer in the future. Cancer of the colon can take several years to develop and detecting it in its early stages is linked to higher survival rates.

Screening consists of doing a test for a condition before there are any symptoms. We screen for conditions such as colorectal cancer if there is good evidence that it will help make a difference to patient outcome. Other examples of these tests include:

  • screening for breast cancer with mammograms even when the breasts seem normal
  • screening for high blood pressure even without a history of heart problems or stroke

Remember, screening is only done if there are no symptoms. If someone has symptoms of colorectal cancer – which can include blood in the stool (may appear as bright red or dark tar-like stool), a persistent change in stool patterns, abdominal pain or unexplained weight loss – other testing needs to be done through a family doctor or specialist.

The kit that your doctor gave you is the fecal occult blood test. The FOBT test is done at home and can pick up trace amounts of blood in the stool. A positive test result needs to be followed up with further investigations with your doctor that may include colonoscopy, and/or referral to a gastroenterologist or surgeon.

I recommend the test to be done every two years between the ages of 50 to 74 if you are at average risk of colon cancer. If you have a family history of this cancer (i.e. in a first-degree relative) it is recommended that a colonoscopy be done for screening instead. Work with your doctor to assess your risk and see what test would be most appropriate for you.

Listen, nobody likes to collect their stool and it may seem "messy" as you note, but the possibility of it potentially saving your life is certainly worth the discomfort. March is colorectal cancer awareness month, for more information about this cancer, screening and your options visit: colonversation.ca

Dr. Sheila Wijayasinghe is the medical director at the Immigrant Womens' Health Centre, works as a staff physician at St. Michael's Hospital in their Family Practice Unit and at Hassle Free Clinic, and established and runs an on-site clinic at Women's Habitat Shelter in Etobicoke.

Click here to submit your questions. Our Health Experts will answer select questions, which could appear in The Globe and Mail and/or on The Globe and Mail website. Your name will not be published if your question is chosen.

The content provided in The Globe and Mail's Ask a Health Expert centre is for information purposes only and is neither intended to be relied upon nor to be a substitute for professional medical advice, diagnosis or treatment.

Interact with The Globe