Thursday, October 21, 2010

Unnecessary testing and thermography

Spotlight-on-Science recently wrote an article about the problems with thermography – you can check it out here. At present many companies exist which offer breast cancer screening by thermography (taking a simple thermal image of the surface skin of the breast), however, finding a medical doctor / radiologist who is equipped to interpret the thermogram image is much harder (and an absolutely necessary step for thermography to be useful to the patient). Unfortunately, thermography has been shown to have a terrible sensitivity to catching cancer though it has received a lot of hype.

Much of the support for thermography has come largely because of one 30-year-old peer-reviewed research paper which says that having an abnormal thermogram is a risk factor for breast cancer. This merely means that if you get a thermogram and the image says you’re abnormal then the chances of you getting breast cancer in your life is substantially increased (compared to what you thought your risk was prior to getting the thermogram). This conclusion doesn’t mean that thermography is a good way to detect breast cancer, it means that an abnormal thermogram indicates you might get cancer at some point in your life. This study is 30 years old and even this conclusion regarding risk factors needs a thorough verification.

Other technologies like x-ray mammography, nuclear medicine and MRI have progressed substantially over the past 30 years and many studies indicate that either MRI or nuclear medicine are the most sensitive methods for detecting breast cancer.

Thermography is not an adequately proven technology, making its use a potentially unnecessary test.  Funny times and  McHumor have some cartoons that complement these ideas:

Jacob Levman, PhD
Imaging Physics Research
Sunnybrook Research Institute
University of Toronto