radiology and imaging
sponsored
New evidence for digital
mammography plus tomosynthesis
Digital breast tomosynthesis, the latest generation technology in breast imaging,
uses a three-dimensional, limited-angle tomographic breast imaging technique to provide
multiple projection views, thus reducing interference from overlapping tissues
From GE Healthcare
Breast cancer accounts for one in three cancers in
women throughout the European Union (EU),
making it the leading cancer site among women
on the continent. With a mean breast cancer
incidence rate of 70.7, western Europe also has one
of the highest incidences of breast cancer in the
world, accounting for 11 of the top 20 countries. 1–3
Screening is the mainstay of breast cancer
detection, with numerous studies finding that
early detection translates into substantially
reduced mortality rates. 4–6
However, current technologies have several
shortcomings. The most common is false-positive
recalls, leading to unnecessary testing and biopsy
procedures. This is particularly true of women
with dense breasts, which can hide a lesion, and
of those with superimposition of fibroglandular
tissue, which can be misinterpreted as a lesion. 7,8
Getting a false positive diagnosis causes
unnecessary anxiety and fear, and women who
receive a false positive result are more likely to
delay their next mammogram. 9
Digital breast tomosynthesis
Digital breast tomosynthesis (DBT), the latest
generation technology in breast imaging, uses
a three-dimensional, limited-angle tomographic
breast imaging technique to provide multiple
projection views, thus reducing interference from
overlapping tissues. These thin slices (at 1-mm
spacing) are then reconstructed to provide the
three-dimensional view.
Numerous observational and clinical studies
attest to the improved specificity DBT offers,
whether used as an adjunct with digital
mammography (DM) or synthetic 2D
mammography, or as a stand-alone screening
technique, as well as its ability to reduce recall
rates while improving cancer detection,
particularly for invasive cancers. 8,10–14
The European Society of Breast Imaging
(EUSOBI) in its most recent position paper on
screening mammography concluded that DBT is
set to become “routine mammography” in the
screening setting in the near future, but also
noted there are several unanswered questions
around the technology. 15
Areas of focus for current research include data
on the challenges of implementing DBT-based
screening programs; rates of overdiagnosis; cost
effectiveness; and, perhaps most important, the
ability of DBT to improve prognosis, mortality,
and morbidity. 16
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HHE 2018 | hospitalhealthcare.com
One of the first prospective, randomised trials
assessing the use of DBT in the screening context
is the Reggio Emilia Tomosynthesis Randomised
Trial. The study is being conducted at screening
centres in northern Italy, and is designed to look
at interval cancers, or those detected between
screening exams, and cumulative incidence of
advanced cancers. 17
Preliminary results published recently provide
additional evidence regarding the benefits of DBT
+ DM versus DM alone. This two-arm, test-and-
treat prospective randomised trial compared DM
plus DBT (experimental arm) with DM alone
(control) in 19,560 women aged 45–70 who had
previously received one round of screening and
had no familial risk of breast cancer. All screening
mammograms were conducted using GE
mammography equipment, including
tomosynthesis. Figure 1 (refer to the next page)
highlights the study design and randomisation.
The authors reported a detection rate 90%
higher in the DBT + DM arm than in the control
arm (8.6 per 1000 women screened vs 4.5 per
1000 screened), with similar recall rates. The
detection rate was higher for ductal carcinoma
in situ (DCIS) than invasive cancer; for invasive
cancers <10mm (84% increase) and ≥10–20mm