The benefits of 3-D Mammography

By Dr. Donald Lien  |  6/15/2018

There are presently 4,272 certified facilities in the nation offering patients digital breast tomosynthesis, more commonly referred to as 3-D mammography, according to the U.S. Food and Drug Administration (FDA). Last May, there were 3,293 facilities with 3-D mammography, a 30 percent increase in one year.

As this technology continues to grow and be offered at imaging centers across the country, it's important to understand what 3-D mammography is and how it differs from the conventional, two-dimensional screenings.

Three-dimensional mammography was introduced and approved by the FDA in 2011. The move by facilities to provide 3-D mammograms, however, has only gained traction in the last four years due to the high cost of the equipment and issues related to insurance reimbursements.

Since that time, several studies have borne out that 3-D mammography has many benefits over 2-D imaging as the technology is better able to separate normal breast tissue from a breast mass. In short, 3-D mammography provides greater clarity and accuracy in detecting breast cancer.    

In fact, current research shows 3-D mammography increases the detection of invasive cancers by 41 percent and decreases unnecessary callbacks – and anxiety - for additional scans and biopsies by 40 percent.

The exam is similar to a conventional mammography as both use X-ray machines that compress the breasts between two plates. The 2-D screening, however, only takes images of the breast from the front and side. This way of taking images can create tissue overlap that can both hide and mimic abnormalities.

In a 3-D screening, the X-ray tube moves in an arc across the breast, taking high-resolution images from multiple angles. Radiologists then view the images in a series of slices that are one millimeter thick. This allows for finer detail and better visibility of breast tissue and obscure lesions. This is especially advantageous to patients with dense breast tissue.

It is normal and common to find dense breast tissue in patients, particularly in young women and those with low body fat. Dense breast tissue appears as a solid white area on a mammogram, making it difficult to see through and note developing lesions. Since 3-D mammography allows radiologists to see small sections of the breast at a time, it is easier to find abnormalities surrounded by dense tissue.

Mammography radiation exposure is tightly regulated by the FDA as set forth by the Mammography Quality Standards Act (MQSA) enacted in 1994. The MQSA dose limit for a screening mammogram is 3 mGy. The approximate dose radiation exposure in a 2-D mammogram is 1.2 mGy and in a 3-D mammogram, 1.45 mGy.

While both are well under the MQSA limit, there is slightly more radiation exposure in a 3-D mammogram when compared to the standard screening.  Even so, the benefits of receiving a 3-D mammogram far outweigh the risks, particularly when you consider the 40 percent reduction in additional screenings.

Studies have shown the five-year survival rate of people with stage 0 or stage 1 breast cancer is nearly 100 percent. That is why it is so important to get screened every year. Putnam Hospital Center is committed to providing state-of-the art technology to improve on the early detection of breast disease and is why the investment was made to bring in a 3-D mammography system. Today, all of the hospital's breast screenings are done using 3-D mammography. Most insurance companies now cover it, too.  

Dr. Donald Lien is a radiologist at Hudson Valley Radiology and Associate Director of the Radiology Department at Putnam Hospital Center. To schedule an appointment, please call 845-790-8855 and press 4. Learn more about 3-D mammography at Putnam Hospital Center.