Mammograms — what’s best for you?
by Dixie Mills, MD, FACS
New recommendations for mammogram screening are raising questions for women everywhere.
It’s important for every woman to understand the benefits and limitations
of screening mammography, so that she can make the choice that’s right for
her. Here are the sections in this article:
Many women were shocked to hear the report recommending a change in mammogram screening
guidelines. After being encouraged to get a mammogram once a year starting at 40
and to check our breasts monthly, it feels like we’re breaking the law, being
deprived, or missing out on some essential rite of passage if we don’t follow
these rules. But a recent report prepared by an independent panel of experts (the
US Preventative Services Task Force, or USPSTF) and published in the Annals of Internal
Medicine, recommends that most women put off mammograms until age 50, and
get them every other year instead of annually.
What is a screening mammogram?
A screening mammogram is a 2-dimensional imaging tool
that uses x-rays to detect breast cancer in women without symptoms.
Regular screening mammograms allow a radiologist the opportunity to detect something
new or see a change in your breast tissue.
I’m the first to admit that this topic is confusing: there is no one simple
message when it comes to mammography. We’ve been told it save lives, then
we hear of a woman who had a clean mammogram three months prior to finding a lump
in her breast and she’s gone in a year. The fact is, having annual mammograms
will not prevent you from getting breast cancer — unfortunately, mammograms
don’t act like brushing and flossing our teeth do to prevent cavities and
gum disease. Mammography will detect some pre-existing lumps, but the technology
(and the experience) is far from perfect. And though many don’t know it, mammograms
do come with some very real risks.
Though early detection through mammography is still the most widely available
tool we have for beating breast cancer, especially for women at elevated risk, mammography
is only a supporting player in good breast health, not the lead role. At Women to
Women we put as much if not more emphasis on optimal nutrition, exercise, and a
healthy lifestyle. In terms of preventing breast cancer, there is a lot of hopeful
research pointing to the benefits of daily exercise, maintaining a healthy weight,
eating soy, and supplementing with fish oil, iodine, and indole-3-carbinol
(a compound found in cruciferous vegetables like broccoli).
What are the new screening mammography guidelines?
- Screening mammograms begin at age 50 and, if normal, are repeated every 2 years
rather than annually.
- Women can stop getting screening mammograms at age 74.
- Decisions about screening mammography for women under 50 and those over 74 should
be discussed with a healthcare provider and based on their individual risk factors.
These guidelines concern routine screening of women in general, and do not apply
to the small percentage of women who are known to be at heightened risk of breast
So what should you do about mammograms? Let’s put the latest information into
perspective, so you can work with your practitioner and make an educated decision
The controversy over mammograms
For every woman I see who declines mammography outright, I see one who wants a mammogram
every month. Both ends of the spectrum are probably a bit too extreme. But all things
being equal (age, family history, general health), which of these patients is more
likely to die from breast cancer — and whom does the mammogram benefit?
Over the past 30 years, mammograms have been shown to decrease breast cancer deaths
in women over 50 years of age by 30%. But a benefit for women in their 40’s
was never clearly demonstrated, begging the question: When is the best time to start
— age 40 or 50?
These are all million-dollar questions, because much of the controversy swirls around
the numbers, and millions of women are asking them.
The USPSTF now recommends that unless women have specific risk factors,
they should start mammography screening at age 50 and obtain a mammogram every two
years, rather than yearly. The Task Force also recommends women discontinue screening
mammograms at age 74. Researchers found that not only did the great majority of
women gain no benefit from yearly screening mammograms, some incur harm from them.
Other recent studies have pointed to overdiagnosis and the emotional toll of false-positives
as drawbacks to yearly mammograms.
But other groups, including the American Cancer Society, the American College of
Radiology, and the Society of Breast Imaging continue to recommend annual mammograms
starting at 40. Let’s look at what’s behind the new USPSTF recommendations.
- New statistical data from computerized models and a number of well-designed, carefully
conducted studies, each with over 10 years of follow-up, showed that mammogram screening
exams would prevent only 1 death in nearly 2000 women aged 40-49, while there would
be 99 false-positive results per 1000 screening exams.
- The hazards from radiation exposure from extra images are also part of the added
harm to this age group.
- Likewise, the studies and statistical analyses showed no difference in survival
among women 50-69 years of age who were screened every 1 to 2 years.
These new recommendations are actually in line with the protocols followed by most
European countries for the last 10 years — and most of Europe does not have
higher rates of death from breast cancer than the US.
In another interesting study reported back in 2005 in the Journal of the National
Cancer Institute, researchers looked retrospectively at almost 4000 women
in the US between the ages of 40 and 69. Much to the surprise of the authors, the
study found that women who underwent regular screening died at the same rate as
those who declined mammograms. Their results suggested there may be some benefit
to regular screening for women who are at an increased risk for breast cancer due
to family history or prior atypical breast biopsy. (See the NCI’s free, interactive
Risk Assessment Tool. As recommended, be sure to discuss the results with
your healthcare provider.)
I think that most women had assumed that the benefit of annual screening was much
stronger and that mammograms were far more effective. Unfortunately, mammograms
don’t provide the direct protection and safety of seat belts or motorcycle
and bicycle helmets. However, if you multiply the number of cancer deaths averted
by millions of baby-boomer women, these small percentages still add up to thousands
of lives saved. What’s a woman to do?
So why not err on the “safe” side?
I heard one 59-year-old woman recently say, “I’ve been getting a mammogram
every year since I was 39, so why stop now?” Despite the news that the death
rate from breast cancer has fallen somewhat, the incidence of breast cancer is still
rising, albeit a bit more slowly. By now, we all have known or have had a friend
who has been diagnosed with the disease, and more and more of us know someone who
died from breast cancer at a young age. Most women are willing to undergo whatever
testing they can to beat the odds of this frightening disease.
False positive: A result that is incorrectly positive when a situation
is in fact normal.
False negative: A result that appears negative when in reality
there is an issue to investigate or treat.
So why am I hearing from more and more patients: “Do I really need that mammogram?”
Aside from the debate about whether mammograms really prevent breast cancer deaths,
there are some downsides to the test.
- Mammograms are uncomfortable (and for some women, outright painful). When my patients
relate some of the humiliating experiences they’ve had while getting a mammogram,
I don’t blame them for never wanting to go back — whatever the risk.
Our breasts are very personal and many of us aren’t that comfortable touching
them ourselves, let alone having them manhandled by an x-ray machine or a bossy
- Mammograms come with high levels of false positives for younger women. It is estimated
that about 10% of mammograms are read as false positives, depending on the age of
the woman, the center, the radiologist, the equipment, and the protocol used to
read the images. This leads to increased anxiety and dread in many women.
- Mammograms can lead to unnecessary procedures. Nowadays, mammograms lead to the
diagnosis of more cancers, but particularly in situ cancers, which are
generally noninvasive (not associated with an increase in mortality). Are they actually
saving lives? Not as many as you may have thought. And many women end up having
unnecessary additional radiation and invasive surgical procedures.
- Mammograms expose us to radiation. Epidemiologists have calculated that cumulative
radiation exposure from yearly screening mammograms commencing at 40 could cause
a net overall increase in cancer deaths. As always, there’s a risk-to-benefit
ratio to consider, and the younger we are when exposed to radiation, the more sensitive
- And then there are the cancers that are missed — up to 30%. Many women have
a false sense of security after being told that their mammogram was normal only
to be shocked to find a malignant lump a couple months later. For more on this,
see discussion of the picture problem below.
The experts really did think mammograms would help us detect cancers earlier and
save lives — and initial studies showed it did just that. As healthcare practitioners,
we all bought into the early detection hypothesis, but we now know that there are
more than five types of breast cancer. Some grow fast and act aggressively in the
body, while others are slow growing. Some types act in ways that make finding them
early on very helpful, while others do not. And we’re even discovering that
some forms of cancer might be better off left undetected!
As I mentioned before, mammography is still the best tool we have for detecting
early breast cancer, especially if you are known to be at heightened risk. But I
hope the women who want to continue with their yearly mammograms out of habit or
because they feel it is safer will discuss this with a trusted healthcare provider,
and balance risks and benefits according to their own health history and beliefs.
Mammography and the “picture problem”
There are reasons why mammograms come with so many false positives and false negatives.
A number of difficulties exist in getting a quality image of the breast, otherwise
known as what best-selling author Malcolm Gladwell calls the “picture problem.”
In the 2�D world of screening mammography, two black-and-white pictures of each
breast are taken. These contrasting views provide some dimension, but little more
than what is up, down, medial, or lateral.
Up until the 1960’s basic x-ray equipment was used to look at the breast and
chest cavity. Compression imaging was introduced in the early 1980’s, which
simplified the process and provided a better view — opening the door to mass
screenings. While the radiation doses have decreased significantly since the 1960’s,
not much else has changed.
Frankly, I’m surprised we’ve progressed from color television to high-definition
TV while women’s breasts are still being imaged with black-and-white x-rays.
Even our children’s video games have better depth and detail than the average
Breast health tips from Women to Women — there’s a lot you can do!
We still don’t know what causes
breast cancer or exactly how to prevent it — it’s definitely
not like lung cancer where there is a clear link to nicotine and stopping smoking
does save lives. But there is certainly more research out there on preventative
measures to keep your breasts healthy.
- If you smoke, stop as soon as you can, and drink alcohol only in moderation.
- Eat healthfully, including lots of fresh fruits and vegetables (especially Brassica
vegetables, which contain indole-3-carbinol — broccoli, cabbage, cauliflower,
turnips, kale, kohlrabi), healthy fats, and lean protein, including soy.
- Take a daily high-quality multivitamin that contains iodine and selenium, plus an
omega-3 supplement like the ones we offer in the Personal Program.
- Exercise 30�60 minutes 4 times per week, keep your
body mass index within a healthy range, and cultivate ways to decrease stress.
- Discuss your family history and unique situation with your practitioner to decide
how often to get a mammogram.
Mammograms are clearest when imaging fatty breasts, which are naturally more prevalent
in older women — usually post-menopausal women not on HRT. Higher hormone
levels naturally cause breasts to be more fibrous and harder to read on a mammogram
— or “dense.” (Perhaps this is the reason mammograms are more
beneficial for older women). How your breasts feel does not always correlate with
how they look on mammograms.
A textbook cancer — or as some doctors would say, one that a medical student
could see — would show up on a mammogram as an irregular white shape, often
called a “mass” or a “nodule.” “Nodes” are lymph
nodes, the little shapes generally seen higher up in the armpit on films. The white
shape shows up best on a background of gray or black, which is fat on a mammogram.
Dense breasts contain a lot of perfectly normal fibroglandular tissue that shows
up as white areas on a mammogram. Part of the “picture problem” with
mammograms of dense breasts is that the white areas created by those fibrous tissues
can conceal a small cancer — like trying to find a polar bear in a snowstorm.
For more information, see our page on
dense breasts and “dense mammograms”.
It’s ideal when women with family histories or other high-risk factors are
screened at a breast center where they’re informed of their results quickly
and, if necessary, additional imaging carried out right away, or they are at least
scheduled right away for follow-up, so the period of waiting without knowing is
minimized. I’d like to think all women will have their testing done this way
Because there’s a lot of variation in how mammograms are read and the element
of both human and technological error is considerable, it’s a good idea to
get a second opinion whenever there’s a questionable result.
What are the alternatives to mammography?
There are other forms of breast imaging in use and in development today that provide
an alternative picture of breast tissue. Some of these imaging techniques are still
experimental, and some are of limited availability, and some are considered more
appropriate for diagnostic rather than screening purposes. But you may be able to
request an alternative, if your mammograms are dense, you’re otherwise at
higher risk, or you do not believe in or want to have mammography.
Sometimes women are recommended to have ultrasound screening or magnetic resonance
imaging (MRI) of their breasts in follow-up to screening mammography. Because these
techniques are generally more costly, not all centers provide them and not all insurance
policies cover them, so you may want to ask your healthcare provider to discuss
all your options — and verify your insurance coverage beforehand if cost is
Some alternatives to traditional mammography
- Digital mammography
- MRI scan
Many institutions are converting to digital rather than film mammography, where
the images are digitized (like a digital camera), which allows them to be readily
called up for review on a high-resolution monitor. It also allows the degree of
contrast and some other image qualities to be manipulated, and computer programs
have been developed to assist in analyzing the tissue changes that take place over
time. Digital mammography offers some significant benefits over film for certain
groups of women — premenopausal women and women with dense breasts, according
to a study published in NEJM. Another benefit to digitizing images is that
it allows a radiologist to view your files from a remote location (helpful for second
opinions). False positives and false negatives are still possible, however, so the
benefits aren’t clearcut, and digital mammography is still not widely available
in some areas.
Thermography, or heat detection, is an old method which newer technology is bringing
back. At this point, very few large studies have looked at thermography. I’ve
encouraged women interested in the test to find an experienced institution that
will correlate their findings with other testing. I personally have seen false positive
and false negative results with different practitioners using different types of
cameras. However, if you know of a healthcare provider accredited in thermography,
it might be something to try.
I always joke that I may be able to become the curator of a mammogram museum before
I die. Technology is advancing by leaps and bounds and breakthroughs that make our
current machines obsolete are sure to occur!
What is the bottom line on mammograms?
Mammography is definitely not as good as anyone thought it could be or as beneficial
as we’d like it to be, but I think we are still better off than we would be
without it. I think it’s prudent to follow the new guidelines and get a mammogram
every other year between the ages of 50 and 74, but it should always be a choice,
not an obligation. If regular mammograms go against your belief system, reason,
or common sense — don’t worry. You will not be arrested or ticketed
and your likelihood of dying from breast cancer is still very small if you decline
There is just no definitive answer on mammograms. What you should take into account
is your own individual health picture: your risk factors, age, breast density, and
your threshold for anxiety and risk. Some women may be comfortable getting a mammogram
only a couple times in their 40’s and 50’s; others may need more regular
If you do decide to get a mammogram, I list some suggestions to get the most out
of it on my blog post,
My dream is that in the near future there will be a simpler, better way to screen
women’s breasts. The good news is that researchers are now studying markers
of cancer (or risk of getting it) in nipple aspirate fluid, blood, saliva —
even urine! And there are many things we can do to create better breast health (see
breast health tips, above). We need to focus our
efforts to find the cause or causes of breast cancer, and prevent it altogether.
Check out the Army
of Women for more information. Maybe I will get to be the curator
of a mammogram museum when I retire!
Our Personal Program is a great place to start
The Personal Program promotes natural hormonal balance with nutritional supplements,
our exclusive endocrine support formula, dietary and lifestyle guidance, and optional
phone consultations with our Nurse–Educators. It is a convenient, at-home
version of what we recommend to all our patients at the clinic.
If you have questions, don't hesitate to call us toll-free at
1-800-798-7902. We're here to listen and help.
Related to this article:
References & further reading on mammograms
Principal Author: Dixie Mills, MD, FACS