Infrared imaging is designed to pick up heat, and to image different degrees of heat in false color to make them easy to pick out. The reason for this is that a developing cancer puts out more heat than most of the rest of the breast; in fact, a developing cancer anywhere in the body puts out more heat than surrounding tissue. There are three main reasons for this difference.
- First, when cells are dividing they need extra blood. Since a major characteristic of cancer is extremely rapid cell division, extra capillaries to the cancer quickly develop. This is called angiogenesis. This node of capillaries will demonstrate more heat than the normal blood supply to the cell, often before the cancer itself can be seen.
- Second, cancer involves an inflammation process, and inflammation is hot. Therefore, more heat will be visible at the location of the cancer itself than in the surrounding capillaries. Thus, you will have a heated circle with a heated point inside it.
- Third, Areas of the breast that have for any reason received a greater dose of hormones than other parts of the breast, or breasts that have received an excess hormone dosage, will show as hotter. That is, if Woman A has had six children, her estrogen has been somewhat reduced for nine months six times in her life, whereas Woman B, who is the same age but has no children, she has not had that four and a half years of freedom from estrogen. "Since the single greatest risk factor for the development of breast cancer is lifetime exposure to estrogen, normalizing the balance of the hormones in the breast may be an important step in prevention." Breastthermography.com. In this situation, even if there is a cancer present, thermography may be able to catch it up to eight years earlier than it could be found in any other way.
 Like any other means of external diagnosis, infrared readings do not absolutely prove the presence of cancer. In fact, if the thermogram shows greater hormone exposure, it may help prevent cancer. A suspicious spot still has to be biopsied, though with increased use of needle biopsy, invasive surgery is less common than it was as recently as ten years ago.
But it is important to remember that Thermography is not a replacement for radiographic mammography. Thermography can read only cells and groups of cells that are fairly near the surface of the skin. A cancer, even a rather large one, that is back near the breast wall will be picked up only with a radiologic mammogram.
In addition to traditional mammography and thermographic mammography, it is also necessary for each woman to learn to know her own breasts and check them once a month. Checking more often than that is counter productive, as it often causes a woman to miss changes that she would notice if she checked less frequently. Also, each woman must have a checkup by an MD at least once a year. Bear in mind that although we tend to think of breast cancer as a middle age or older woman's disease, in fact over 23% of all breast cancer is found in women under 30, and those cancers tend to be the most aggressive. It is never safe for a woman to assume that because she has no known risk factors she will not get breast cancer; almost 75% of all breast cancer is found in women without known risk factors.
Do not panic if your doctor or the women's health center where you get your cancer screening mammogram suggests that you also should have a thermographic mammogram. This does not mean that you have cancer. It merely means that your health practitioners are wanting to be sure you are completely safe.
by Anne Wingate, Ph.D. References Breast Thermography. http://www.breastthermography.com/ (3 Jun 2009).
Crawford, Caroline. "Cancer scan catches illness 8 years early." http://www.independent.ie/health/latest-news/cancer-scan-catches-illness-8-years-early-1369649.html (3 June 2009).
Mammography. http://www.radiologyinfo.org/en/info.cfm?PG=mammo (3 June 2009). |
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