Lower colorectal cancer screening age to 45 from 50, Canadian Cancer Society urges

TORONTO – Michael Groves thought he had appendicitis. 

In January 2021, he went to the emergency department with abdominal pains, but after testing, medical staff ruled it out and he went home.

A couple of days later, Groves, who lives in Ottawa, saw blood in his stool, so he told his family doctor. 

Both the pain and bleeding stopped, but she decided to schedule the 49-year-old for a colonoscopy for that April to be on the safe side. 

“The idea that it could be colon cancer, that never came to mind,” Groves said in an interview. 

He was put under for the procedure and when he woke up, the gastroenterologist told him he had a five-centimetre tumour. 

Groves was diagnosed with Stage 3 colorectal cancer. It had spread to two lymph nodes. 

“The shock was just, like, wow, just devastating.” 

At that point, he had no symptoms. 

“I went for like a 5K run, I was feeling great,” Groves said. 

“I wasn’t tired. It was just a normal guy in his 40s.”

He had surgery to remove “about a foot” of his colon and then began a gruelling six-month chemotherapy regime. He was off work for almost nine months. 

Now 54, Groves believes that if there had been routine screening for colorectal cancer in his 40s, his tumour would have been caught at a much earlier stage and taken less of a toll. 

He’s one of a growing number of people the Canadian Cancer Society says is getting colorectal cancer before the current routine screening age of 50. 

On Wednesday, the society called on provinces and territories to lower the colorectal cancer screening age to 45.

It said people under 50 are two-to-2.5 times more likely to be diagnosed with colorectal cancer than they were in previous generations.

“That growth is something that’s very concerning for us and we think that it’s time for governments to react to that so that we can catch more of these cancers early,” said Brandon Purcell, advocacy manager for prevention and early detection at the Canadian Cancer Society, in an interview. 

In routine screening, people 50 years of age and older get a fecal immunochemical test — or FIT — to swab their stool at home and send the swab in a postage-paid envelope to a lab.

If the sample tests positive for blood in the stool, that person is referred for a colonoscopy to check for cancer.

People younger than 50 who have specific risk factors or symptoms, including a family history of colorectal cancer or blood in the stool, are often sent for proactive colonoscopies.

But for everyone else, providing a FIT to those 45 years and older will allow for earlier detection of colorectal cancer, when the survival rate can be as high as 90 per cent, the cancer society said. 

The survival rate is less than 15 per cent when it’s found in advanced stages, it said. 

In addition to tumours, colonoscopies can also find precancerous polyps and remove them before they become dangerous. It takes eight to 10 years for a polyp to develop into cancer, said Barry Stein, president and CEO of Colorectal Cancer Canada, which is also calling for routine screening to start at age 45. 

Both the Canadian Cancer Society and Colorectal Cancer Canada pointed to a recent modelling study as the latest in a growing amount of evidence supporting a younger screening age. 

The study, published March 7 in the Journal of the Canadian Association of Gastroenterology, estimated that starting the home-based fecal immunochemical test at age 45 could potentially prevent 15,070 colorectal cancer cases and 6,100 deaths over the next 45 years. 

Senior author Darren Brenner, a professor in oncology and community health sciences at the University of Calgary, said the research also estimated a cost savings of $233 million in cancer treatments, even after accounting for the costs of doing additional FIT tests and colonoscopies.

This report by The Canadian Press was first published March 11, 2026.

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