Breast cancer screening should start at age 40, says Canadian Cancer Society

All provinces and territories should lower the starting age for breast cancer screening to 40, the Canadian Cancer Society said Thursday.

Some provinces already pay for mammograms starting at age 40, but current guidance set by a national task force recommends starting breast cancer screening at age 50.

It’s critical that women across the country have “timely access to breast screenings, no matter where they live,” said Sandra Krueckl, executive vice president of mission, information and support services for the cancer society.

“There is strong enough evidence from trials, from modeling studies and from real-world data to justify that change to 40,” Krueckl said in an interview.

“We’ve been hearing for a long time that there are concerns about (women) ages 40 to 49 and their ability to access (screening).”

About 13 per cent of breast cancer cases in Canada occur in women in that age group, Krueckl said.

Earlier diagnosis often means less invasive treatment is required and results are more successful, he said.

The Canadian Task Force on Preventive Healthcare, which establishes clinical guidelines to help family physicians and nurse practitioners decide if and when to suggest screening, currently recommends routine screening starting at age 50 for people with average risk of breast cancer.

The task force is scheduled to review its guidance this spring, but said in an email that a “detailed” review of clinical trials, international best practices and other data is still underway and did not confirm what the updated advice will be.

“The Canadian Task Force respects the Canadian Cancer Society and its important work,” he said.

“We look forward to discussing draft breast cancer screening recommendations from our comprehensive evidence review later this spring.”

Even if the task force recommends that screening begin at age 40, it is ultimately up to provinces and territories to fund it, the cancer society said.

It is also “critically important” for primary care providers to talk to their patients about breast cancer screening starting at age 40 and not wait until they turn 50, Krueckl said.

“We also know that black women are more often diagnosed before age 50 and with more advanced disease,” she said.

One in eight women in Canada is expected to be diagnosed with breast cancer in her lifetime, the cancer society says.

These are the starting ages for breast cancer screening in each province and territory, according to the Canadian Cancer Society:

• In British Columbia, Nova Scotia, Prince Edward Island and Yukon, women can self-refer for breast screening starting at age 40.

• Screening is available starting at age 45 in Alberta and the Northwest Territories.

• Ontario and New Brunswick have committed to lowering the minimum testing age from 50 to 40 in 2024.

• Saskatchewan has said it will reduce eligibility for screening at age 40 in a “gradual” approach starting in 2025.

• Screening programs in Manitoba, Quebec and Newfoundland and Labrador continue to begin at age 50

• Nunavut does not have an organized breast screening program.

This report by The Canadian Press was first published May 9, 2024.