Breast Density, Mammography, and New Technologies in Breast Imaging

Accurate breast imaging technologies have been a hot political issue in the world of medicine for the last decade. With the re-evaluation of the effectiveness of mammograms by the American Cancer Society in 2009, experts have begun to debate whether mammography is indeed a flawed technology, providing less than accurate diagnostic information in many cases. In addition, annual mammograms subject the patient to damaging levels of radiation and often, steep health care bills. The heart of this issue is not modern medicine's politics and practices, however. The real issue is how to detect breast cancer in the majority of women early enough to save lives.

Deborah Rhodes, a physician at the Mayo Clinic, became passionately involved in the field of breast imaging technology when one of her pregnant patients found a breast lump, which fortunately was benign. The patient posed the question of how she would be able to know if any future mass was benign or malignant? How confident was Dr. Rhodes that any tumor would be found on a mammogram in this young woman?

This began a journey of partnership between members of a number of disciplines, putting their heads together in order to adapt existing technologies for more accurate breast imaging. What these researchers came up with was a technique called Molecular Breast Imagining (MBI).

Although still in the testing phase, MBI uses gamma technology, and promises to be a very important imaging option because of a few critical key features:

·         It is highly accurate for women who have dense breasts.

·         It uses a radioactive tracer which is taken up by rapidly dividing cells, leaving normal cells alone, and uses the molecular characteristics of tumors which highlight abnormal tissue irrespective of breast density.

·         Another added bonus-only light, pain-free compression is used to obtain images!

One crucial fact for women to know before they opt for a mammogram is that the higher your breast density, the lower the accuracy of your mammogram. This is a fact that has fueled the controversies over what age is most appropriate to begin screening women with mammography. Of women in the 40-50 age range, two thirds tend to have dense breast tissue, as do women using hormone replacement therapy, as well as one-third of women who are postmenopausal. As women age, the breast tissue tends to become less dense and more fatty, making mammograms more accurate for these women.

Breast density tends to be genetically determined. High breast density itself is a greater risk factor for breast cancer than having a mother or sister with breast cancer. Although this information is very important, it has not been widely discussed and patients are rarely informed of the health implications of their breast density.

Both tumors and dense breast tissue appear white on a mammogram, so it's very difficult to distinguish between the two. According to Dr. Rhodes, mammograms find over 80% of tumors in fatty, low density breasts but as few as 40% in extremely dense breasts. Even the much acclaimed advent of digital technology has not shown an increase in accuracy over traditional mammography, except in the group of women under age 40 with dense breasts. In this group, mammograms still found only 60 % of breast lesions.

We have essentially two groups of women—women who mammography works well for and women for whom it does not. This issue has been highly politicized. So much so that the findings of Dr. Rhodes team were initially rejected for publication by four major peer reviewed journals, and finally after challenging possible vested interest interference, accepted by the Journal of Radiology.

If you can detect a tumor when it is less than one centimeter, chances for survival are 90%. MBI can find tumors as small as 3 mm, and MBI finds three times more tumors than mammography can detect in women with dense breasts. In a recent comparative study of 1000 women with dense breasts, mammography found 25% of breast tumors, and MBI found 83% of breast tumors. Needless to say, this is a huge difference in accuracy.

Let's look at what other technologies are currently available and the pros and cons:

·         Ultrasound is noninvasive but has a high false negative rate, generating more biopsies that turn out to be benign.

·         MRI generates over a thousand images, which makes it very sensitive, but very expensive to interpret. If used to screen the average young woman it would cost ten times what a digital mammogram costs. The health care system cannot afford to offer this method as a general screening modality.

Either of these may be appropriate for you after mammography if you need or want further imaging and/or have other risk factors that increase your breast cancer risk.

·         Thermography: thermal imaging of breast tissue shows abnormal vascularity and heat patterns. This can be provide very useful information but may also miss small or slow growing tumors.

The fact of the matter is we desperately need new imaging technologies. The MBI imaging system, which has already been FDA approved, can fill in that crucial gap in accuracy for women with dense breasts. Experts are estimating five more years before it is widely available.

MBI technology, as exciting as it is, still exposes the breast to radiation equaling the dose of one digital mammogram. If you would like to find out more information about MBI, you will find Dr. Rhodes' video on TED talks.

What you should know:

·         Know your density. Ask your practitioner or get a copy of your last mammogram.

·         If you are premenopausal, schedule a mammogram in the first half of your menstrual cycle when your breast tissue is less dense.

·         Consider adding thermography as another screening modality.

·         Screening should be individualized based on breast density and other risk factors.

·         Discuss having additional imaging with your health care provider, especially if you feel there is something unusual in your breast.

Hopefully researchers in this field can help work towards the development of screening technologies that do not involve radiation to the breast. There needs to be more freedom and less politicization of women's breast imaging by mainstream medicine. Thermography should be much more widely researched, so we have better understanding of its potential strengths and weaknesses.

None of our current breast imaging technologies can provide everything we need in a screening tool. None are both accurate enough and safe enough, so it's important to understand all of available options for a comprehensive baseline screening that is as close to accurate as possible.

For this reason, I would like to offer you my free Wellness Guide providing critical information about breast health diagnosis and treatment. It is my hope that this information can offer valuable guidance for women of all ages in their quest for better breast health, naturally.