As its name implies, breast thermography measures differences in temperature and this is accomplished by means of an infrared sensor. The technology has been around for fifty years but is now readily accessible, from an affordability perspective, because an infrared camera costs just a thousand dollars. The rationale for applying thermography is that breast cancers tend to stimulate angiogenesis, the growth of small blood vessels into a tumour, thus providing it with oxygen and nutrients. The additional blood flow results in additional heat. The metabolism of breast cancer cells tends to be more rapid, while cancer is also associated with inflammation. For all these reasons, the temperature of breast cancer tissue is likely to be higher than the surrounding healthy tissue.
So, breast thermography is scientifically plausible. Since the woman being imaged is not exposed to any ionizing radiation, nor are her breasts subjected to uncomfortable compression, the technique may therefore be considered preferable to mammography. Because the different tissue temperatures can be colour-coded, cancerous lesions should be readily apparent (see image below). Although the Food and Drug Administration (FDA) cleared breast thermography thirty years ago, their approval was limited to its use as an additional diagnostic tool.
Just a year ago the FDA stated that it was unaware of any valid scientific evidence to show that thermography, when used on its own, was effective in screening for breast cancer. “Mammography is still the most effective screening method for detecting breast cancer in its early, most treatable stages,” said Dr Helen Barr, a director at the FDA’s Center for Devices and Radiological Health. “Women should not rely solely on thermography for the screening or diagnosis of breast cancer.”
As we have discovered, there is no shortage of health care providers making inappropriate claims about the benefits of thermography. We leave the final word to Dr Barr: “While there is plenty of evidence that mammography is effective in breast cancer detection, there is simply no evidence that thermography can take its place.”