What is a 3D mammogram?
Hint: This screening can help your doctor detect breast cancer earlier
Early detection is the key to identifying cancer when it’s more easily treated and curable, especially with breast cancer. For many years, early detection in breast cancer depended on self and clinical breast exams as well as regular mammograms (2D mammograms).
But in recent years, technology has improved and provided healthcare professionals with a more advanced tool for breast cancer detection: 3D mammography.
“3D mammography, which is also known as digital breast tomosynthesis or DBT, takes multiple X-ray images of each breast from many angles, creating a layer-by-layer view of the breast tissue,” says Dr. Anne Dunne, a diagnostic radiologist at Geisinger Medical Center in Danville.
The images from this form of mammography reduce tissue overlap that may hide cancers. They also reduce the chance that overlapping normal tissue in the breast can create a shadow on the mammogram that can look like an abnormality.
Standard mammogram vs. 3D mammogram: What’s the difference?
A 3D mammogram is different from a standard mammogram in the same way computerized tomography differs from a standard X-ray – it’s a 3-dimensional perspective that can provide doctors with a clearer, more accurate view compared to standard mammograms.
“Mammograms usually consist of two X-rays of each breast, top to bottom and side to side,” says Dr. Dunne. “3D mammography machines take multiple pictures of each breast from many angles, with the X-ray tube moving in an arc above the breast.”
3D mammograms are designed to overcome some of the limitations of standard mammograms.
With a 3D mammogram, the breast is positioned in the same way as a conventional mammogram. Compression of the breast is still necessary to produce the best quality images. Both the time it takes to perform the mammogram and the radiation dose to the patient are not significantly different than a standard mammogram.
3D mammography is credited with earlier detection of cancers that may be hidden on traditional mammograms, as well as improved accuracy in identifying the shape, size and location of abnormalities in the breast.
Increased accuracy means fewer “callbacks”
“At times, patients are called back to the imaging center for additional views and/or a breast ultrasound to evaluate an area of concern on the screening mammogram. Most of the time, these areas are caused by overlap of normal breast tissue and not breast cancer. The process of being called back for additional testing can be very stressful and anxiety-provoking for the patient,” says Dr. Dunne. “A 3D mammogram reduces the need for callbacks since it can tease through the layers of breast tissue in one-millimeter increments.”
Women with dense breasts may benefit from a 3D mammogram
While any woman needing a breast screening can get a 3D mammogram, they’ve been found particularly helpful in improving breast cancer detection in women with dense breast tissue.
“Breast cancer is often the same density as the normal breast tissue surrounding it. Since cancerous tissue and normal tissue can be the same density, a cancer can ‘hide’ on a conventional mammogram. Tomosynthesis increases the likelihood of being able to detect the cancer as different from the normal breast tissue. This can make breast cancers more apparent and less likely to be hidden by the surrounding normal tissue,” explains Dr. Dunne.
In fact, researchers have found that 3D mammography increases the breast cancer detection rate by as much as 41 percent, depending on the type of cancer.
So, should you get a 3D mammogram?
The images that a 3D mammogram provides can help your doctor detect cancer earlier when it's easier to treat. Check with your insurance provider to make sure they cover a 3D mammogram and talk with your doctor about what’s best for you.
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