Quebec plans to keep using mammography machines that are under scrutiny across the border in Ontario, despite questions about their effectiveness in detecting breast cancer.
On Tuesday, hours after Ontario announced it would spend $25-million to replace the 76 machines across the province and encouraged women to get retested, Quebec Health Minister Réjean Hébert insisted such actions were unnecessary.
“There is no evidence at this time that mammography equipment used in Quebec offers lower performance,” Mr. Hébert said in a prepared statement in French.
The machines at issue are used primarily in the two provinces, and employ a digital technology known as computed radiography or CR that, according to a first-of-its-kind study, is 20-per-cent less effective at detecting breast cancer than other devices.
Three-quarters of Quebec’s 144 mammography machines, or 108, use CR technology, according to the province.
By contrast, about a quarter of Ontario’s 316 mammography machines are CR devices.
The remainder either use traditional screen-film technology that produces black-and-white X-ray images or another form of digital technology called direct radiography, or DR. The study, conducted by Cancer Care Ontario, found both detect breast cancer at the same rate.
Mr. Hébert said Quebec was taking the findings of the study, published in the journal Radiology, “very seriously” and the province would consult experts to determine the best course of action.
In no other province are CR devices as ubiquitous as in Ontario or Quebec.
Manitoba, Saskatchewan, Newfoundland, Nova Scotia and Prince Edward Island have none. Just one of the 41 breast-screening sites in British Columbia uses CR technology.
Alberta estimates that 3 per cent of its machines are CR, and New Brunswick counts three of its 22 machines. Officials in both provinces said they are considering phasing out the machines in light of the study.
Ontario’s heavy reliance on CR machines drew harsh criticism from the Ontario Association of Radiologists, which called the funding announcement a “Band-Aid” and accused the province of ignoring recommendations the association made in 2010 to phase out CR machines and adopt the DR technology.
“In most of the provinces, it has been recommended for a number of years [to move to DR] and radiologists there have been able to get their message heard,” association president Dr. Mark Prieditis said. “In Ontario, that’s extremely difficult to do.”
The group’s recommendation was not based on the performance of CR machines, but rather that the more expensive DR machines were preferred by radiologists and that Ontario ought to keep pace with the rest of the country.
Ontario Health Minister Deb Matthews in an interview denied flouting the group’s recommendations, noting that hospitals and private clinics that do screenings decide which technology to purchase.
CR and DR machines made their way into hospitals and clinics around 2005, and today cost about $250,000 and $330,000, respectively, according to the province.
“We fund hospitals. We fund clinics. But we don’t buy their machines,” Ms. Matthews said, adding later: “We are in this case because we’re saying you can’t use those [CR machines] any more.”
CR machines remain approved for use by Health Canada. Of the 76 in Ontario, five are in hospitals and 71 are in private health clinics, according to the province.
The Canadian Breast Cancer Foundation applauded the province’s move, and encouraged Quebec and others to follow suit. “We would absolutely like to see governments across the country take the initiative and move from CR machines to DR machines in as expedited a manner as possible,” said foundation co-chief executive officer Sandra Palmaro.