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courtesy: Are you dense |
Nearly 20
plus years of research have provided sufficient evidence to link dense breast
tissue and increased risk of missing cancer diagnosis by screening mammography.
As the breast density increases, the reliability of mammogram as a screening
tool for picking up breast malignancy decreases.
What is
meant by “being dense”? Breast density does not correlate with physically
palpated firmness of breast, it is a radiologic finding and cannot be predicted
without obtaining a mammogram.
Mammographic breast density is defined as the
relative amount of radio-opaque (white) elements to radiolucent (black) fat on
the image. Increase in the proportion of radio-opaque elements leads to greater
mammographic breast density.
Radiologists
find it difficult to distinguish between tumor and normal dense tissue, both of
which appear white on a mammogram.
In fact, mammography
will only detect 30% cancer in dense breasts and 80% in non-dense breasts.
Nearly 40%
of women have dense breast, which means that only using mammography as a
screening tool puts this population at high risk of missing the diagnosis,
delayed diagnosis or diagnosis at very late stage of disease. A recent search of
PubMed revealed nearly 3,027 studies on masking risk of dense breast tissue.
Increased
density of breast is a casual as well as masking risk factor for breast cancer.
According to the American Cancer Society, having heterogeneously or extremely
dense breast tissue puts you at risk of breast cancer that is equivalent having
one first-degree relative with breast cancer. (2.1 to 4 times the normal risk)
Also, women
with dense breast are put at increased risk of developing contralateral breast
cancer and interval cancer (cancer detected within 12 months of a normal
mammogram)
A recent Breast
Cancer Surveillance Consortium study noted that breast density exceeds all
other risk factors like obesity, family history and delayed childbirth.
About 28
states in USA have passed law regarding the mandatory reporting of breast
density and the necessary follow up thereafter, after women have a screening
mammogram.
So, is there
a standard protocol for supplemental screening if a woman is diagnosed of
having dense breast on screening mammogram? No, unfortunately not, the medical
community has not agreed on a protocol regarding supplemental screening for
women with dense breasts.
In a
position statement, the ACOG, identifies dense breast as a moderate risk factor
but does not support routine use of adjunct screening modalities in an average
risk woman with dense breast. The American Cancer Society urges the patients with dense breast to talk to healthcare providers about additional screening
modalities and advises an MRI along with her yearly mammogram in a high-risk group.
The American
College of Radiology identifies breast density as a controversial risk factor
for breast cancer with no consensus that it confers sufficient risk to warrant
supplemental screening.
At this
time, it is highly suggested that patient should initiate a dialogue with her
physician, regarding the protocol to be followed after the diagnosis of dense
breast. Each patient should be individually evaluated about her risk of breast
cancer based on her genetics, family history and other risk factors.
One
suggested approach based on a paper presented by Lee C. at Society of Breast
Imaging/American College of Radiology Breast Imaging Symposium; April 26, 2015;
Orlando, FL is to use tomosynthesis for all levels of risk, supplemental
whole-breast ultrasonography for women with average risk, and supplemental
magnetic resonance imaging for women with intermediate and high risk
For women
who are at high risk and also have a contraindication to magnetic resonance
imaging, whole breast ultrasonography or molecular breast imaging, if available,
may be an appropriate alternative.
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courtesy: https://www.moffitt.org/media/6369/125.pdf |
The current
options available in addition to screening mammography are Tomosynthesis or 3D
mammography, Ultrasound, Magnetic Resonance Imaging (MRI), Molecular Breast
Imaging (MBI) or Breast Specific Gamma Imaging (BSGI) and Contrast Enhanced
Spectral Mammography (CESM)
Nancy M.
Cappello, Ph.D. has founded Are You Dense, Inc., and Are You Dense Advocacy, Inc.,
to educate women and general public about the challenges women with dense
breast face regarding the screening tools for detecting early breast cancer.
Classification of Breast Density: American College of Radiology.
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