Breast thermography, or thermal imaging, is a noninvasive and painless test that doctors sometimes use to monitor for early breast changes that could indicate breast cancer. It works by detecting increases in temperature.
Thermography does not involve radiation. Instead, it uses an ultra-sensitive camera to produce high-resolution, infrared photographs, or heat images, of the breast.
Thermography first appeared in the 1960s, but it has struggled to gain ground as a diagnostic tool for breast cancer due to concerns about poor sensitivity and inaccurate results.
The authors of a 2018 study noted that the sensitivity of infrared imaging technology had improved drastically in recent years. They concluded that it may show promise for the future but that, for now, people should only use it alongside other screening methods.
Health authorities, including the Food and Drug Administration (FDA), have issued similar recommendations.
Read on to find out more about thermography, including what it involves and its benefits and risks.
Thermography uses digital infrared imaging to detect subtle changes in the breast by revealing areas of heat and cold.
In the body, areas of high or fast blood flow will show on a thermograph as being warmer than other areas.
When blood flow increases for this purpose, the skin in that area will become warmer. A tumor will, therefore, appear as a hot spot in thermography images.
According to the American College of Clinical Thermology, thermography can detect changes that may indicate various conditions, such as:
- fibrocystic disease
- an infection
- vascular disease
The test cannot confirm that cancer is present. It can only show that there are changes that may need further investigation.
However, the FDA do not recommend using thermography without another screening method.
They stress that "thermography is not an effective alternative to mammography and should not be used in place of mammography for breast cancer screening or diagnosis."
Thermography should always take place in a doctor's office or another healthcare setting.
It will involve the following:
- The person will stand about 6–8 feet away from the camera.
- They will have a painless, noninvasive test that does not involve compressing the breast.
- The procedure will last approximately 15 minutes.
The practitioner will look for clear differences between the breasts. For this reason, thermography might not be suitable for a person who has undergone a mastectomy or other breast surgery.
The FDA note that other facilities, such as spas and homeopathic clinics, are also carrying out thermography services.
The FDA express concern that these providers may be giving "false information that can mislead patients into believing that thermography is an alternative or better option than mammography."
This incorrect information may result in people not obtaining a correct diagnosis in the early stages of breast cancer when treatment is usually most effective.
Anyone who opts for thermography should ask a doctor to recommend a provider and also attend mammogram screening as the doctor recommends.
What can you expect during a mammogram? Find out more in our step-by-step guide.
What thermographs detect
A thermograph will not detect a lump, but it will show changes in body and skin temperature, which may be a sign of increased metabolic activity or blood flow in one particular area.
These changes happen as the cancer cells strive to maintain themselves and grow.
If the results show something unusual, this may not necessarily be cancer. The cause could be mastitis, a benign tumor, fibrocystic breast disease, or another issue.
If the thermography detects any abnormalities, the person should seek further screening, which may include a mammogram. If a mammogram confirms that a lump is present, the doctor may recommend an ultrasound or MRI scan and a biopsy.
Only a biopsy can confirm whether cancer is present.
What happens in a breast biopsy? Learn more here.
As a screening option for breast cancer, thermography offers the following benefits:
- It is not painful.
- It is not invasive.
- It does not involve radiation.
Thermography itself does not appear to pose any physical risk to a person, but there can be other risks.
The authors of a review article noted both that thermography produces a high number of false-positive and false-negative results and that estimates of its sensitivity vary widely.
They concluded that, overall, thermography was "not sufficiently sensitive" to use as a diagnostic tool.
False-positive results can result in anxiety and unnecessary follow-up procedures. They could occur if there is another issue, such as mastitis.
False-negative results can give the impression that breast cancer is not present when it is, which may result in late diagnosis and a lower chance of effective treatment.
The FDA echo these concerns.
Some organizations that provide thermography may not provide a person with all of the information that they need, potentially resulting in a false sense of security.
They may give the impression that they are monitoring the person's health, when, in fact, they are not making the person aware of the whole picture.
Some people say that thermography is better than mammography because it is a "natural" method that avoids exposure to radiation.
Mammography screening guidelines try to balance the risk of the small amount of radiation a person will receive with that of finding breast cancer when it is too late to treat it effectively.
Consequently, they recommend more frequent screening for people who have a higher risk of breast cancer.
Lack of scientific evidence
The authors of a systematic review concluded that there was not enough evidence to support the use of thermography as a screening method for breast cancer, either alone or in combination with of other screening methods.
The authors were unable to find enough suitable data to assess the tool effectively. They noted that some studies receive sponsorship from industries supporting the use of thermography, which can lead to biased results.
How does thermography compare with mammography? Find out more here.
Health authorities do not currently recommend using thermography to replace mammogram screening. If a person undergoes thermography, doctors urge them also to have a mammogram.
Mammography remains the "gold standard" to screen for early signs of breast cancer. Although it is not always accurate, more scientific evidence supports mammography than thermography.
Breastcancer.org note that researchers are looking into new types of thermography that may, one day, prove reliable.
Until then, however, it is best to choose a screening method that has scientific evidence to support its effectiveness.
Some women in our family had breast cancer at an early age, and they did not survive. I am concerned about my daughter, who is 18 years old. I don’t want her to start having mammograms — even if the insurance would cover them — and I was thinking about thermography. What do you suggest?
Anyone with a family history of breast cancer should consider genetic testing to check for mutations in the BRCA gene, which can increase breast cancer susceptibility. The results will allow a doctor to provide more information on options to reduce the risk of breast cancer through surveillance and surgical methods.
Mammography is a screening method for women with an average risk of breast cancer. Due to the lack of scientific evidence to support thermography, experts do not recommend it as a screening method, even for women at average risk.Christina Chun, MPH Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.