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New breast ultrasound screening equipment at Mercy Imaging Centers finds breast cancer in a patient with dense breasts who had a normal mammogram.
Multiple studies of screening mammography over the last 30 years from multiple continents demonstrates it
lowers the mortality from breast cancer by about a third
in screened women in comparison to women not getting
Studies also demonstrate the ability of screening
mammography to find early invasive stage 1 cancers depends on a woman’s breast density, or percentage of
fibroglandular breast tissue in comparison to fatty breast tissue. It may be able to detect 90% of early cancers in women
with predominately fatty breasts, or less than 25% fibroglandular tissue, but may detect only 50-60% of
early cancers in women with extremely dense breasts,
or greater than 90% fibroglandular issue.
Since about 40% of women have dense breasts,
meaning greater than 50% of the breast tissue is
glandular in comparison to fat, the lower sensitivity of
mammography in these women is a significant problem affecting a large percentage of the screened population.
Adding to the significance is about 70% of breat cancer occurs in women with dense breasts. In fact, the risk of breast cancer in a women with
extremely dense breasts in comparison to a women
with fatty breasts is elevated 4-6 fold. This means
these women have a similar increased risk of developing
breast cancer as the increased risk of a women with a
1st degree relative diagnosed with breast cancer.
In summary, women with dense breasts are common,
they account for the majority of breast cancers, they
are at higher risk of developing breast cancers, and
mammography is less able to diagnose their cancers
At Mercy Imaging Centers, we understand the statistics and the
limitations of screening mammography. However, we do not accept that women with dense
breasts will have their breast cancers detected at later
stages resulting in more aggressive surgery and therapy
and a lower chance of survival.
Multiple studies using physician-performed, hand-held
ultrasound have demonstrated that early invasive breast
cancers can be detected on ultrasound that were not
seen on mammography. In these studies, the number of
cancers detected with ultrasound nearly doubles the
number found with mammography alone. However, for many reasons, physician performed
screening ultrasound is impractical.
Fortunately, technology is available that can acquire
ultrasound images of the entire breasts in asymptomatic
women with dense breasts and the images acquired can
be reviewed by a radiologist trained in breast imaging. Using this ultrasound technology, a recent study of over
6000 examinations in women with dense breasts
resulted in mammography detecting 17 of 39 cancers,
while adding this technology, 35 of the 39 cancers were
identified, an improvement of 100%, which is similar to the studies using physician-performed hand-held
We recently purchased this technology called automated whole breast ultrasound (AWBUS) from a company called SonoCine. To date, 70 women with dense breasts and a recent
normal mammogram have chosen to have this study
performed. Last week using this equipment, we found a 1 cm invasive
lobular cancer in a woman with dense breasts who had a
normal mammogram less than 2 months earlier. Of note, invasive lobular cancer is often diagnosed late
using mammography. We would anticipate this patient
being a candidate for breast conservation therapy and
likely being cured from her cancer.
We recommend consideration of automated whole breast
ultrasound as an adjunct screening examination in
asymptomatic women with dense breasts in addition to
screening mammography, not as a replacement for
The study takes about a half hour, is
painless, and requires no breast compression or
This automated whole breast ultrasound (AWBUS) is
Mercy Imaging Women’s Center
Coyle Avenue, Ste. 360
Carmichael, CA 95608
Please contact Daniel Herron, MD, Director of Women’s
Imaging at [email protected], if you
have any questions, concerns or suggestions.
1. Kelly K. Breast Cancer Detection Using Automated Whole Breast Ultrasound and Mammography in Radiologic Dense Breasts Eur Radiology 2010 March;20(3):734-741.