She died of breast cancer. She said it didn't have to be that way

Before Tanja Harrison died of breast cancer, she left the world with a dire message: supplemental screening could have saved her life.

Following a routine mammogram in 2021 that came back clear, the Nova Scotia woman learned she had dense breasts and requested supplemental screening — an MRI or ultrasound — to ensure her dense breast tissue was not concealing something nefarious. 

It can be difficult for mammograms to pick up cancers in people with dense breasts because dense breast tissue and abnormal breast changes such as tumours both show up as white areas on the imaging. 

Harrison was denied the screening. Two years later, she discovered she had Stage 4 breast cancer with extensive bone metastases. She was told it was not curable. The 53-year-old mother and wife died on Dec. 2. 

"She had every reason to be angry that the health-care system failed her … but I can honestly say there was no anger," said Kim Harris, Harrison's friend of 40 years.

"That is pretty incredible when you sit back and think about it."

Harrison's plight is being touted by advocates as an example of why supplemental screening should become standard for women with dense breasts as several provinces move toward offering the additional screening.

Dense breast tissue has relatively high amounts of glandular and fibrous connective tissues and relatively low amounts of fatty breast tissue as seen on a mammogram — an X-ray used to screen for cancer. Density is categorized A through D, with C and D being considered dense breasts.

Breasts with a higher density are also more prone to cancer.

Advocates have long argued that ultrasounds or MRIs should be regularly provided for women with dense breasts because they can pick up irregularities a mammogram cannot. 

Harrison, a former university librarian, felt if she had received supplemental screening when she asked for it, she may have had a chance to fight for remission.

Following her diagnosis, she started working with the advocacy group Dense Breasts Canada, telling her story outside Province House in March 2024 as Opposition Liberal MLA Rafah DiCostanzo tabled a bill to implement a supplementary screening program. The bill did not make it past first reading.

Harrison's championing of the cause in the face of her terminal illness and declining health speaks to the type of person she was, said Harris.

"It was just very typical Tanja, always wanting to pave the way for those coming behind her," Harris, who is originally from Nova Scotia, said in a recent interview from her home in Regina.

Nova Scotia has historically been a leader in the country when it comes to breast cancer screening. It is one of only two provinces with a high-risk breast cancer screening program. 

Patients with dense breasts who have a greater than 25 per cent risk of breast cancer can access mammography and supplemental MRI screening. Factors that increase someone's risk of breast cancer include family health history, whether the patient carries a certain gene, and breast density.

But Jennie Dale, executor director of Dense Breasts Canada, said simply having dense breasts should be enough for those patients to get supplemental screening.

She said mammography misses about 40 per cent of cancers in women with dense breasts.

"Women must get additional screening, and that is what is being denied to them," said Dale in a recent interview. "They are not told it's not accurate. They are not warned that they need to be vigilant if they see anything, feel anything. They need to be their own advocate."

The provincial Health Department declined an interview request.

But in a statement, the Nova Scotia Breast Screening Program said ultrasound is not offered as part of any organized screening program in Canada, "as there is insufficient evidence to support its use as a supplemental screening modality for dense breasts in a population-based breast cancer screening program."

"It may be available in certain parts of Canada in private clinics or at other sites with capacity to provide it, but it is not provided as a routine screening test in an organized fashion," the statement said.

Following a meeting of Canada's federal, provincial and territorial health ministers last week, Nova Scotia Health Minister Michelle Thompson said the province is adhering to clinical practice guidelines.

"We need to follow the science and the evidence," Thompson told reporters when asked about supplemental breast cancer screening.

"We're not holding anything back, but we are working with those experts who understand the science, understand the process and who are adhering to clinical guidelines."

What's happening elsewhere

However, some regions in Canada are moving toward offering supplemental screening outside of breast cancer screening programs, and a provincial health committee in Ontario has recommended publicly funding it.

In a statement, Alberta Health Services said health-care professionals should consider an annual breast ultrasound for women with extremely dense breast tissue. These decisions are made on a case-by-case basis.

The office of the chief public health officer in the Northwest Territories said it aligns with Alberta's best practices. 

British Columbia's Provincial Health Services Authority said although its breast screening program does not recommend supplemental testing in the form of an ultrasound, it is available with a provider referral.

Supplemental screening is also not currently part of Ontario's breast screening program, but people with category D breasts can talk to their family doctor about being referred for additional screening outside of the program, Ontario Health said in a statement.

In December 2023, Ontario Health — based on guidance from a technology advisory committee — recommended publicly funding supplemental screening as an adjunct to mammography for people with extremely dense breasts. 

The province's Ministry of Health is reviewing the recommendation. In an email statement, it would not elaborate on what stage the review is at.

Jean Seely, a professor of radiology at the University of Ottawa, was an adviser on the committee.

Seely said the panel determined that although providing supplemental screening comes with a big price tag — as much as $41 million over five years for MRIs — providing care to patients with later stage breast cancer through treatments like radiation and chemotherapy is more costly.

It also reduces the emotional and physical toll on the patients if cancer is found earlier. According to the Canadian Cancer Society, it's estimated that about one in eight Canadian women will develop breast cancer during their lifetime and one in 36 will die from it.

"It is worthwhile to be able to diagnose women with dense breasts with early stage breast cancer because it's not only good for them — they're more likely to survive and do well — they also require far less treatment costs," said Seely in a recent interview.

"The cost of treatment skyrockets when you diagnose cancer at Stage 3 compared to Stage 1 — it's $49,000 versus $200,000 to $300,000 for their lifetime."

Seely, who also leads the breast imaging section at the Ottawa Hospital, said the panel reviewed a number of international studies in arriving at the recommendation.

But she acknowledged that supplemental screening has not yet been proven to reduce mortality rates, as that is still being studied and it takes time to measure those rates.

Nevertheless, she feels women with dense breasts should have the option for an MRI every two years. It is already happening with referrals through primary care providers in her region of Ottawa, she added, although wait times are long.

Harrison spent some of her final days fighting for women with dense breasts to have the option of supplemental screening.

Harris said she has been amazed by the response to her friend's story, and she feels a sense of duty to carry on her advocacy.

"She was very spiritual. We would joke about the tricky universe sending us messages," said Harris. "Fifteen minutes after she passed, I got a very strong sign from her."

That sign was hearing Forever Young come on the radio as she drove away in Tanja's car — a song they bonded over in high school.

"I just know very strongly she would want us to do this."