Colorectal cancer signs, symptoms & screening: Everything you need to know about the 2nd deadliest cancer in Canada

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Colorectal Cancer Awareness Month is back this March, and one non-profit is encouraging Canadians to learn more about the disease and how its screened. That includes understanding how colorectal cancer can be preventable, treatable and beatable if caught early.

For March, Colorectal Cancer Canada launched a new campaign this year called Make Your #2 Your #1 Priority. "Our objective is to make all Canadians aware that colorectal cancer can affect everyone, that it exists and 69 Canadians each day are diagnosed," the non-profit stated in its campaign, which focuses on changes in bowel movements.

President and CEO of Colorectal Cancer Canada Barry Stein urged people to take their health into their own hands because screenings can save your life. "No one should wait until symptoms appear because, by then, it may be too late," the stage four colorectal cancer survivor shared in a news release.

Stein previously shared five things Canadians should and shouldn't do when it comes to managing their health and preventing colorectal cancer. Those included everything from paying attention to symptoms and maintaining a healthy lifestyle.

Colorectal Cancer Canada is also urging people to wear blue on Friday, March 7 in support of people impacted by the disease. Similar to last week's Pink Shirt Day to raise awareness around bullying, the organization's Dress in Blue Day aims for people to wear a blue-coloured clothing item — anything from a T-shirt to socks — to help spread awareness about colorectal cancer.

Canadian screening policies recommend average-risk adults get screened for colorectal cancer at age 50 and above. However, rates of the disease in younger people have been rapidly rising worldwide. Even celebrities like former Dawson's Creek star James Van Der Beek, who was diagnosed with stage three colorectal cancer last year when he was 47, have faced the disease head on.

In Canada, an estimated 25,200 people were diagnosed with colorectal cancer last year. The Canadian Cancer Society indicated that represents 10 per cent of all new cancer cases diagnosed last year, adding that around 9,400 people died from the disease in 2024. In the U.S., there may be more than 154,000 new colorectal cancer cases diagnosed in 2025.

One Canadian who experienced colorectal cancer at an early age is Ontario-based rapper Bishop Brigante. The Scarborough, Ont.-bred artist was first diagnosed with colorectal cancer in October 2023.

"I'm 45. I could've been fighting this in my 30s," Brigante previously told Yahoo Canada. "I could've been fighting this sooner and it would've been a completely different fight."

In late January 2024, Brigante created a petition urging medical professionals and policymakers to push for a lower age criteria when it comes to colonoscopies in Canada. At more than 37,000 signatures, the petition urges for that criteria to be set at age 30, specifically for men.

But what exactly is colorectal cancer and should Canadians worry about developing the disease? Read on to learn more.

What is colorectal cancer?

Colorectal cancer is a disease that affects your large intestine (colon) or your rectum (the end of the colon). Colon and rectal cancers are grouped together as colorectal cancer because the two organs are made of the same tissues without a distinct border between them.

When cells in the colon or rectum no longer grow or behave normally, the changes may lead to non-cancerous tumours, precancerous conditions (i.e. adenomas) or colorectal cancer.

What are the warning signs and symptoms of colorectal cancer?

Colorectal cancer may not present any significant signs or symptoms in its early stages, making it all the more important to stay up-to-date on your colon health and get screened regularly. If caught in its early stages, colorectal cancer is 90 per cent curable.

According to the American Cancer Society, a polyp can take as long as 10 to 15 years to develop into cancer. Therefore, symptoms often only start appearing once a tumour grows and affects the surrounding organs and tissues. The early signs of colorectal cancer are often similar to other health conditions, including anemia and irritable bowel syndrome.

Dr. Monika Krzyzanowska, a medical oncologist at the Princess Margaret Cancer Centre, told Yahoo Canada in a previous interview that one of the early signs of the disease is a change in bowel habits: "[People] may not be going as often [to the bathroom] as they usually do. The calibre of your stool may change. For example, it can become thinner or more narrow."

Krzyzanowska noted abdominal pain, bleeding and unexplained weight loss are causes for concern, alongside iron-deficiency anemia: "One of the things people may not know [to pay attention to] is iron-deficiency anemia. They may be feeling tired, go see their family doctor and are found to be anemic. This can sometimes be an initial presentation of colon cancer."

Other signs or symptoms of colorectal cancer may include:

• Diarrhea

• Constipation

• Narrow stool (compared to average)

• Blood in the stool

• Unexplained weight loss

• Anemia

• Abdominal cramps and pain

• Nausea and vomiting

• Pain or discomfort in the rectum

• Bleeding from the rectum

Krzyzanowska indicated the urgent symptoms you should never ignore are "any sort of severe abdominal pain or abdominal pain associated with nausea, vomiting and an inability to pass stool," as they could be symptoms of a bowel obstruction.

Who is at risk for colorectal cancer?

While colorectal cancer can affect anyone, people living with inflammatory bowel disease such as Crohn's disease or ulcerative colitis are at an increased risk compared to others. Risk factors include a family history of polyps and colon cancer, obesity, smoking, alcohol, sedentary behaviour and a diet high in processed food and red meat.

"Ironically, a lot of the lifestyle factors [that are good for colon health] are good for other things as well," Krzyzanowska said, adding that "having a healthy diet, not smoking and having a good weight" can decrease your risk of the disease.

Why are more young people dying of colorectal cancer?

For 2025, the American Cancer Society projected the United States will see more than two million new cancer diagnoses, which equates to about 5,600 new cases per day. Moreover, there could be more than 618,000 cancer deaths this year, according to the organization's annual cancer statistics report. Despite this growth, no one can say for certain why colorectal cancer numbers are increasing amongst young people.

However, some experts theorize increased incidence rates could be linked to sedentary lifestyles, obesity, smoking, heavy alcohol use, environmental factors and poor diets. Still, learning your family history of colorectal cancer, getting regular medical checkups, exercising and consuming a good diet are all key to leading a healthy life.

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