What is 3D mammography?
3D mammography, also known as tomosynthesis, is an innovative screening and diagnostic tool for breast cancer. While conventional mammograms produce flat, two-dimensional images of the breast, 3D mammography takes a series of multiple images to form a 3D picture of your breast tissue in as little as one-millimeter slices. These detailed images allow the radiologist to scroll through the breast tissue, layer by layer, and obtain a more accurate overall picture of the breast.
What to expect during your exam
“The patient experience for a 3D mammogram is very similar to a standard mammogram,” said Dr. Bradley Johnson, medical director of the imaging department at Providence St. Mary Medical Center in Walla Walla, Washington. “The extent and length of the exam and the compression required is almost identical to a 2D exam.”
For most patients, a 3D mammogram complements a conventional 2D mammogram. Both exams are performed at the same time with the same breast compression. To achieve 3D images of the breast, a machine moves in a swift and sweeping arc over the breast, taking images from various angles. It takes only few seconds to complete this portion of the exam.
Benefits of 3D Mammography
Fewer Call Backs
“Decreased recall or ‘call-backs’ is the biggest immediate impact of 3D mammography,” said Dr. Johnson.
Calling a patient back for additional testing is a considerable drawback to conventional mammography. On average, 10% of women are called back because of something suspicious spotted on their standard mammogram. These additional tests can be worrisome to patients and are notoriously associated with false alarms – up to 80% of recalls from a standard mammogram don’t lead to a cancer diagnosis.
Studies show that 3D mammography can cut call-backs by 50%. Because of tomosynthesis’ improved clarity, precision and a more overall accurate picture of the breast, radiologists can now rule out certain abnormalities without additional tests or screenings.
“That’s certainly been the case at our center where our radiologists’ recall rates averaged 11-22% with conventional mammography,” said Dr. Johnson. “Now, with the new technology, our call-back rates have decreased to 5-14%.”
By reducing call-backs, 3D mammography helps decrease false alarms, saving time, health care costs and ultimately helps diminish unnecessary patient anxiety caused by the additional testing.
Improving Cancer Detection
“Individual case studies clearly demonstrate that 3D mammograms can detect cancers that aren’t visible on conventional 2D mammograms,” said Dr. Johnson. “But statistically, it will take a number of years before we know exactly how much this new technology will increase cancer detection and how that will affect the rate of breast cancer survival.”
Current studies show a small, yet real increase in cancer detection. “And more importantly,” said Dr. Johnson, “this increase is in the detection of invasive breast cancer.”
Invasive cancer is characteristically more aggressive, likely to spread or be fatal. Women have a greater survival rate when breast cancer is detected early and is still localized in the breast. Tomosynthesis notably improves the discovery of small masses and architectural distortions associated with invasive cancers.
Is a 3D mammogram right for me?
3D mammography is suitable for all women who would have a standard mammogram for both screening and diagnostic needs. In other words, if you’re a good candidate for conventional 2D mammography, you’re a good candidate for tomosynthesis.
Tomosynthesis allows radiologists a better, more definitive evaluation of breast tissue for all breast types. But in particular, women who have dense breast tissue may see added benefits of 3D imagery in both the reduction of call-backs and overall cancer detection.
“Dense breasts can be difficult to evaluate mammographically,” said Dr. Johnson. “But the images produced by 3D mammograms allow radiologists to page through the layers of the breast tissue, like flipping through a book. This really provides an added edge for finding hidden lesions in a dense breast.”
For women who aren’t at high risk for breast cancer, the American Cancer Society recommends annual mammograms beginning at age 40, and should continue as long as the woman is in good health.
Is the radiation dose greater during a 3D mammogram?
Very low X-ray energy is used during a 3D mammogram. The dose is slightly greater than 2D exams, but is well below the FDA limit for mammography. The Federal Drug Administration (FDA) approved breast tomosynthesis in 2011.
Is a 3D mammogram covered by insurance?
Insurance coverage varies from plan to plan. Providence St. Mary Medical Center offers 3D mammograms almost exclusively. Patients, however, are billed for a standard 2D mammogram and aren’t charged the additional fees to perform a 3D exam.
How do I schedule a 3D mammogram?
Doctor referrals aren’t required for mammograms. Women can schedule their own screening mammograms, and provide the name of the primary care doctor they want the report sent to. Low income women may qualify for free screening mammograms through the Lifesaver Fund maintained through the Providence St. Mary Foundation.
Patients in the greater Walla Walla area can schedule a 3D mammogram or learn more at (509) 522-5850.
To find out if 3D mammography is available in your area, talk to your primary care provider or call your local Providence breast care center.