Breast Tomosynthesis: 3D Mammography
We are excited to offer breast tomosynthesis 3D mammography at the Breast Center at Centennial Medical Center, the first and only site in Middle Tennessee to offer this promising new technology.
Although mammography is currently the most accurate screening tool available for breast cancer detection, its sensitivity is limited in dense tissue, which can hide cancers. The 3D images largely eliminate the problem of tissue overlap and therefore significantly increase cancer detection accuracy.
The 3D mammograms are obtained on a specially equipped digital mammography device. While the patient is in compression for conventional 2D mammogram, the camera moves in an arc, taking pictures every 15 degrees. The computer then reconstructs the images at 1 mm intervals, much like CT or MRI. The addition of the 3D pictures to the 2D picture takes only an extra 4 seconds per compression.
The radiation dose for the entire examination is very low, equivalent to living in Denver for 3 months.
By seeing the tissue at each level, radiologists can help to uncover what is hiding. For patients with dense tissue or high risk, this can be performed as a screening test. For patients with abnormal screening mammogram, it can clarify whether or not there is truly an abnormality and can clearly localize it for further study or biopsy. As this is a special form of testing, it does require a physician's order. Also, because this is such new technology, insurance may or may not cover it.
This technology was just approved by the FDA in February 2011, and the Centennial Breast Center is the first center in Middle Tennessee (and among the first in the country) to offer it.
If you would like more information or would like to know if you qualify for breast tomosynthesis, please call the Centennial Breast Center at 342-5018.
Why Is Mammography So Important?
It is estimated that one in eight American women will develop breast cancer at some time in her life, so this is an issue that affects all of us. It has been conclusively demonstrated that screening mammography significantly decreases the breast cancer death rate. It does this by finding breast cancer in the earliest, most curable stage. Unfortunately, breast cancer is not always easily identified and often requires an entire arsenal of imaging techniques to identify and evaluate it.
Mammography has long been the mainstay of breast cancer screening. It is non-invasive, safe, widely available, and relatively inexpensive, so it is an excellent tool for widespread screening. However, conventional mammography is hampered by the fact that it is two-dimensional imaging of a three-dimensional structure. Overlapping tissue, especially if it is dense, can readily hide a cancer. Conversely, overlapping tissue can create the appearance of a suspicious abnormality where none exists. Even digital mammography, which has much better resolution than the old film-screen mammography, still has the limitation of tissue superimposition. This is where breast tomosynthesis 3D mammography really shines, because it removes the problem of overlapping tissue and significantly increases the accuracy of mammography.
For more information on mammography, click here.
What About Breast Ultrasound?
Breast ultrasound is very helpful if there is a specific area of concern, since it may show abnormalities hidden on mammogram. It is particularly helpful in distinguishing between cysts (always benign) and solid masses (which may be benign or cancerous). However, ultrasound does not give a global picture of the entire breast. Current technology limits the picture to the tissue directly under the probe, so the search has to be confined to the site in question. Although there has long been an effort to develop effective whole-breast ultrasound, that technology is not yet fully developed.
What About Breast MRI?
Breast MRI does give a global view of the entire breast, showing both anatomy and physiology. However, it requires injection of intravenous dye, because MRI's major function is to demonstrate differences in blood flow between normal tissue and cancer. MRI often shows abnormalities which are silent on mammogram or ultrasound, but mammograms can sometimes show abnormalities which are silent on MRI. Although very effective and helpful in certain situations, MRI is not utilized for widespread breast cancer screening because of the cost and invasiveness of the procedure.
For more information on Breast MRI, click here.