Health Canada has issued a warning on thermography-based breast imaging to Canadian citizens and healthcare providers.
Thermography uses infrared technology that shows patterns of heat and blood flow on or near the surface of the body. Some healthcare practitioners have been promoting thermography devices as substitutes for conventional mammography screening.
However, thermography is not approved to screen for breast cancer in Canada, as Health Canada pointed out in its November 28 warning. The agency went on to say that it "is not aware of any clinical evidence that thermography can be used effectively as a screening technique for the early detection of breast cancer."
What's more, thermography may present a potential risk to women who rely on the results, the agency said. Health Canada advised women who have received the scans for breast cancer screening to contact their physicians "for appropriate follow-up and testing."
The agency went on to say that it is following up with the manufacturers of thermography devices to ensure that they know it's illegal to market the systems for breast cancer screening in Canada. The agency is also working with Canadian border control authorities to stop unlicensed products from entering the country.
The advisory came the day after CBC News issued a news report on "dozens of clinics" across Canada offering thermography for breast exams. A CBC News reporter went undercover posing as a patient to have the test at a clinic, where she was informed by a nurse of the benefits of thermography over mammography, the report said.
The report noted that false positives generated by the scans are "gumming up" the healthcare system, and quoted clinicians and public health authorities who were critical of the effectiveness of the tests.
The U.S. Food and Drug Administration (FDA) in 2011 issued an advisory on thermography, warning consumers and physicians that the technology is not approved as a substitute for conventional mammography.
