Medical clinics across the country are touting the benefits of a diagnostic test for breast cancer that medical experts say is useless.
A CBC News investigation has identified dozens of clinics offering thermography for breast examinations.
Proponents of the test believe it can detect breast cancer years earlier than mammography.
Gillian Bromfield, senior manager of cancer control policy at the Canadian Cancer Society, says thermography tests fail to detect most cancers and generate false positives. (CBC)But medical authorities worldwide say there is no proof that thermography actually works as a diagnostic tool for cancer.
They say false positives from thermography tests are gumming up the system, resulting in patients worrying about the results of tests that have no value. Alternatively, the tests may be giving others a false sense of security about their health.
"It's not effective at detecting breast cancers," said Gillian Bromfield, senior manager of cancer control policy at the Canadian Cancer Society.
"It misses the large majority of breast cancers and, on top of that, it also detects cancers when there actually are none."
Regardless, some Canadian clinics continue to make startling — and unproven — claims about the benefits of thermography.
The U.S. Food and Drug Administration has sent out warning letters to those making similar assertions south of the border, but there has been no such action in this country.
Heat-sensitive imagery
Thermography uses a heat-sensitive infrared camera to take images of the body.
Those images are then assessed elsewhere, often in the U.S. After a wait of several days, patients are informed of their test results.
The service is provided at dozens of facilities coast to coast in Canada.
Claims used to promote the service are not accepted by the mainstream medical community.
Health Scan Digital Thermography Clinic, for example, offers the test in Ontario.
The company's website makes a number of assertions about thermography:
- "Earliest method of possible breast cancer detection known."
- "Can detect a pathologic state of the breast up to 10 years before a cancerous tumour can be found by any other method."
Stamina Clinic in Lethbridge, Alta., says thermography is not a substitute for mammography, but "can be an invaluable tool for earlier detection of breast disease" — especially for women in their 20s and 30s.
Thermography is offered by dozens of clinics across the country. (CBC)"Thermography is a vital screening tool for younger women (20-45 years) whose denser breast tissue makes it more difficult for mammography to be effective," the clinic notes on its website.
"There is a rise in breast disease in younger women and thermography offers a safe alternative without harmful effects of radiation for this age group."
Integrated Health Clinic in Fort Langley, B.C., says in promotional text that "thermography's role in breast cancer and other breast disorders is to help in early detection" and monitoring of physiology that is considered abnormal.
"It is used as part of an early detection program to give women of all ages the opportunity to increase their chances of detecting breast disease at an early stage," the company's website notes.
And thousands of kilometres away, in St. John's, Avalon Laser Health offers thermography scans at $215 a pop.
A CBC News undercover reporter went to the clinic to have the test, and was informed by the nurse of the benefits of thermography over mammography.
Avalon Laser Health later removed text on its website dealing with thermography's role in screening for breast cancer after being questioned about those claims by the CBC.
Contacted afterward, the clinic said the nurse provided the wrong information.
Test is 'actually useless'
Medical experts take issue with claims trumpeting the benefits of thermography in diagnosing breast disease.
Nancy Wadden, a St. John's doctor who chairs the mammography accreditation program of the Canadian Association of Radiologists, says women are paying big money for a test that is "actually useless."
Nancy Wadden chairs the mammography accreditation program of the Canadian Association of Radiologists. She says the "useless" thermography tests add to waiting times for women who actually need treatment. (CBC)Wadden says that women who actually need treatment face longer wait times because of women who register false positives after thermography.
"These women have a significant number of false positives, so then they are coming and they are clogging up my ultrasound list and my mammogram list and then displacing the people who really need to have the test, who are waiting there," Wadden said.
"Their length of time to get a diagnosis is prolonged, because we've got people who have had this useless test that has given a false positive result."
Regulatory action south of the border
In the U.S., regulators have sent warning letters to those making unproven claims about thermography.
In April 2011, the Food and Drug Administration sent one of those letters to Peter Leando, president of Florida-based Meditherm Inc.
The FDA took issue with how the company was marketing its Med2000 thermography device, specifically objecting to the claim that it could "increase your chances of detecting breast cancer in its earliest stages."
The health regulator also took issue with the claim that the device was "FDA approved."
Peter Leando, president of Florida-based Meditherm Inc., says thermography provides an early warning. (CBC)In an interview with CBC News, Leando downplayed the warning letter.
"That was in relation to some wording on a website which they weren't happy about," he said.
"And that wording was changed immediately. I think the wording was related to 'accurate,' and something else. And we just changed the words so that it wouldn't be likely to mislead anybody into thinking that it was accurate in the detection of breast cancer. We've got to make sure that nobody actually makes claims as far as a stand-alone diagnostic test."
Leando says the Meditherm system is used by roughly 100 locations in Canada, and about 4,000 worldwide.
Australia recently removed the Med2000 from the country's medical device registry. Leando, however, says the firm deregistered it voluntarily.
Leando says criticisms of thermography — such as those coming from the Canadian Cancer Society — ignore its role as a type of early warning system for "suspicious changes," and detecting abnormalities.
"So that's the whole role of thermography, in giving us the opportunity to intervene, to treat, to actually do something before there is a tumour that is dense enough to be seen with mammography or ultrasound," Leando says.
Meditherm's website continues to reference thermography's role in breast cancer and other breast disorders: "to help in early detection and monitoring of abnormal physiology and the establishment of risk factors for the development or existence of cancer."
Health Canada role
Asked about its role in the thermography debate, Health Canada says it approves medical devices and prohibits false or misleading advertising of health claims.
A federal spokeswoman says Health Canada takes action if a manufacturer makes misleading claims.
But she says it's up to the provinces to take action against clinics that are doing the same thing.
Breast cancer survivor Linda Venus believes there should be more stringent oversight of thermography. (CBC )Meanwhile, there is no evidence that Health Canada has gone after any manufacturers producing devices related to thermography.
That's not good enough for breast cancer survivor Linda Venus, who says there should be more stringent oversight of thermography.
The Winnipeg woman calls the current situation "a vacuum in the regulatory structure of the health system that is supposed to protect us from scoundrels, basically."
Venus says the issue needs to be addressed.
"They are allowed to be there, and there is no governing body anywhere that can prevent them from being there," she said.
"And providing women with false information — and in some cases, false hope."
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