Advances in Imaging: 3D Digital Breast Tomosynthesis

Posted on October 2017

For nearly 50 years, mammography has been the gold standard for breast imaging. This routine test has proved to be simple, inexpensive, and readily available across the world. However, that may change in the near future when more results are in on the newest technology, 3D digital breast tomosynthesis, which is currently available in all eight of UW Health’s breast imaging locations. Tomosynthesis is showing great promise to become widely recognized as an overall better imaging tool.

“More studies are showing us that tomosynthesis improves our ability to see cancer over standard mammography,” said Mai Elezaby, MD, assistant professor in the UW School of Medicine and Public Health Department of Radiology’s Breast Imaging Section. With the near-three-dimensional imagery it provides, radiologists have more nuanced imaging available to review and make diagnoses.

The technology used to image breast tissue to detect cancers has made great advances since the 1970s, when screen film mammography was the detection mode of choice for breast cancer. Standard mammography is a two-dimensional technology that primarily outlines the edges of the tissue. Since then, advancements in technology presented us with digital imaging, which improved on the earlier film-based mammography, making it possible to diagnose cancer in younger patients and patients with dense breast tissue. “What’s certain is that data from numerous studies since the beginning of mammography in the 1970s support that screening with standard mammography detects breast cancers when they are small enough to provide the best results with treatment,” Elezaby said.

However, standard mammography (2D) is not perfect. Sometimes standard mammography does not detect all cancers, giving false negatives. The most recent improvement in this technology is digital breast tomosynthesis, also known as 3D mammography. “Tomosynthesis gives us the ability to look through the breast in multiple layers,” Elezaby said. “Studies have shown that this new way of imaging improves the ability to see cancers and in particular, better see cancers that matter more,” Elezaby continued. “Overall, it has improved our performance of making the diagnosis of invasive cancer by 40%.”

In addition to helping radiologists to better see and diagnose cancers, tomosynthesis has had additional diagnostic benefits. “When we use a standard 2D mammogram, if we would see something of concern in their imaging, we would call patients back to clinic for further testing, whether it be more imaging or even biopsies where a big proportion end up being false-positive benign disease,” Elezaby said. “With 3D tomosynthesis, we have seen about a 17% drop in false-positive recalls and unnecessary imaging.”

Tomosynthesis is as safe as a mammogram, delivering superior imaging with the same amount of radiation exposure. The main difference is that with tomosynthesis, the radiation is split to enable multiple views from more angles, making it more efficient.

“As a research institution, we look for information to prove one diagnostic procedure is better than another,” Elezaby said. “More studies are looking into the long term benefit of 3D tomosynthesis over standard mammography. We are eagerly looking forward to the results of these studies , but all indications say 3D tomosynthesis will improve upon the performance of the standard mammogram.”

Not all health care providers and insurance companies are on board yet with this new technology. “It is our hope across UW Health that more and more caregivers continue to embrace tomosynthesis,” Elezaby continued. “And likewise, that insurance companies step up their coverage. At this point, it is covered 100% by Medicare, but not all insurance companies will cover it,” she added.

Breast Imaging Section Chief Elizabeth Burnside, MD, also sees the value of this new technology. “UW Health is dedicated to enhancing the patient health experience as we strive to improve outcomes ,” she said, “3D tomosynthesis enables radiologists to avoid false alarms without sacrificing early and accurate breast cancer diagnoses.”

3D tomosynthesis is available at all UW Health breast imaging locations and is becoming more frequently recognized as a first-line screening tool for breast cancers. Patients can ask their primary care doctor to have their next breast exam using digital breast tomosynthesis.