woman getting a mammogram, overdiagnosis, breast cancer survivors, hormone replacement therapy

Here we go again. The mammogram debate has once again heated up because of new research (Canadian National Breast Screening Study) casting doubt on the value of this routine cancer screening technique. In a nutshell, roughly 90,000 women were randomized to receive a breast exam plus mammogram or only a breast exam. The goal of the study was to determine whether locating abnormalities before they were large enough to feel during a breast exam would save lives. The women were followed for up to 25 years. At the end of that timeframe, there was no discernible difference in deaths due to breast cancer between the two groups of women.

Here, in the investigators’ own words, were the results:

“During the entire study period, 3250 women in the mammography arm and 3133 in the control arm had a diagnosis of breast cancer, and 500 and 505, respectively, died of breast cancer. Thus the cumulative mortality from breast cancer was similar between women in the mammography arm and in the control arm.”

Their Conclusions:

“In conclusion, our data show that annual mammography does not result in a reduction in breast cancer specific mortality for women aged 40-59 beyond that of physical examination alone or usual care in the community. The data suggest that the value of mammography screening should be reassessed.”


Equally disconcerting were the data on overdiagnosis of breast cancer. An accompanying editorial titled “Too Much Mammography” in the BMJ (Feb. 11, 2014) by distinguished Norwegian epidemiologists and biostatisticians noted:

“No difference in breast cancer mortality was observed between the mammography and control arms, whereas a significant excess incidence of invasive breast cancer was observed in the mammography arm, resulting in 22% overdiagnosis. This means that 22% of screen detected invasive cancers would not have reduced a woman’s life expectancy if left undetected.”

Such a message is hard for most women to comprehend. For decades people have been told that the earlier a cancer is detected, the better the outcome, and this seems logical. In other words, early detection equals improved longevity, perhaps even a cure. Delayed detection was supposed to make it harder to treat or cure a cancer. This study upsets that conventional wisdom.

Not surprisingly, there has been substantial criticism of the study. The American College of Radiology has come out swinging:

“…the recent breast cancer screening article (Miller et al) published in the British Medical Journal (BMJ) is an incredibly misleading analysis based on the deeply flawed and widely discredited Canadian National Breast Screening Study (CNBSS). The results of this BMJ study, and others resulting from the CNBSS trial, should not be used to create breast cancer screening policy as this would place a great many women at increased risk of dying unnecessarily from breast cancer.”

The American radiologists complain that the machines that were used were outdated, the mammogram quality was poor, the technologists used improper positioning techniques and the radiologists “had no specific training in mammographic interpretation.”

Others have described the study as rigorous and impressive. Gina Kolata, writing in The New York Times, described it as “one of the largest and most meticulous studies of mammography ever done.”

Needless to say, women are caught in the middle of this ferocious debate. Should they continue going in for their annual mammograms or are they a waste of time and money? It comes down to the question of whether mammograms save lives. This Canadian research and other studies suggest that the benefits are modest at best. Russell P. Harris, MD, is an expert on screening mammography. He notes that mammography may reduce breast cancer deaths, as calculated from this study and others, by one woman in 1,000 who start screening in their 40s, two in 1,000 who begin annual mammograms in their 50s and three in 1,000 who start undergoing mammograms each year in their 60s. That means the overwhelming majority would not benefit.

Again, this comes as a huge shock to most women. Why is it that detecting breast cancer early doesn’t dramatically improve outcomes? In part it could be because many breast cancers can be treated successfully regardless of whether they are found before they can be felt. Modern treatment has improved. We now have anti-estrogen medications such as tamoxifen, raloxifene and letrozole that reduce the likelihood of a recurrence.

There may also be a surprising number of breast cancers that would not kill regardless of when they are detected. For decades we have assumed that a cancer diagnosis was by definition a potential death sentence. More recently we have learned that there are breast cancers, prostate cancers and even lung cancers that will not ever cause mischief (JAMA Internal Medicine, Feb., 2014). Left alone, nothing bad will happen. That is hard for most people to understand or accept. It is the overdiagnosis issue described in the BMJ editorial above.

Then there are nasty cancers. Even when caught early and treated aggressively, they cannot be cured. For reasons that remain mysterious, some cancers metastasize and kill people despite early detection and excellent treatment. And there’s the rub. Our ability to determine which breast cancers, prostate cancers or other tumors are truly dangerous is quite limited. As a result we treat them with surgery, chemotherapy and/or radiation. Perhaps for most cancers, this is appropriate, but it is definitely overtreatment for some tumors and woefully inadequate for many other malignancies.


We need far better techniques to discriminate between dangerous cell growth and indolent tumors that will never progress to harm us. We also need far better treatments. The mammography controversy is distracting us from these goals.

We welcome your thoughts and your stories below. We recognize this is a very complicated and emotionally fraught topic. Nevertheless, we believe it deserves attention since so much effort and money is directed to screening.

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  1. Mary

    This past late March of 2014, I discovered a lump. I thought OH CRAP! Called up my Well Woman who quickly faxed over an order to the hospital where I go to for my yearly mammogram. Had the procedure done. Finally was able to get in to see my Well Women during the middle of April, 2014. I told my Well women that I wanted this lump taken out. I then told one of the ladies that I do my volunteer with at the Church Food Pantry. She quickly took me aside. Told me to call up her cancer Dr. was able to get in very fast. Meet with the Dr., had another sonogram and mamogram done.
    Come to find out, that I had this lump since 2013. The hospital were I always get my mamogram done told me everything was fine. Nothing was found. Boy, was I ever shaken up by that news. The lump is only 5 milimeter. Which the Dr. says is teeny tiny. Will go back in November for another sonogram and mamogram. The Dr. told me it is benign. I’m happy to hear about that. She is really keeping on eye on this one. Since my grandmother died of the disease. I’m so thankful that I mentioned this problem to the volunteer. Ladies it is very important to keep up the breast self examination every month. Please do it.

  2. KB

    I am a Certified Clinical Thermographer and trainer. While many Thermographers do advertise that Breast Thermography is an alternative to mammography, we do not. Mammography detects lumps at about the size of a pea. It takes, sometimes 6-8 years for a lump to get that large. Conversely, Breast Thermography looks for the unhealthy changes in the breast that may someday lead to that growth.
    Thermography is about BREAST HEALTH and education. It should not feed on the fear of breast cancer. Did you know there is a way to keep your breasts healthy? You can actually be proactive about breast health! Imagine if you never brushed your teeth or used toothpaste or flossed; and then just went to the dentist once a year for your “yearly mouth x-ray” to see if you had cavities or needed teeth pulled. Ridiculous right? The current breast screening system looks JUST LIKE THAT to those of us in the Thermography world!
    When it comes to breasts, women are in constant fear because they do not have any education about how to proactively keep their breasts healthy. They are at the mercy of the yearly mammogram … HOPING that it’s negative. Thermographers empower women to take control of their breast health! This is how we beat cancer… not by finding a lump with radiation after its been growing for years! Thermography looks at inflammation, clogged ducts, sluggish lymph, fibrocystic breasts and hormonal imbalances… all which can contribute to unhealthy breasts. Mammography cannot see ANY of that! Then we teach you how to dry brush your breasts, use creams that move lymph, balance your hormones, adjust your diet, add breast healthy supplements and change your lifestyle to promote breast HEALTH not feed the fear of breast cancer!
    40,000 women per year die of breast cancer – and that is sad – but that number really hasn’t changed much since the start of mammography. More women die of unintentional accidents than breast cancer. Over 400,000 women die of heart disease per year (that’s 10 times more than breast cancer)…but the fear is all on the breast cancer side. The October “pink washing” contributes to and heightens this fear. Bottom line: Mammography is not saving lives… it contributes to over diagnosis and treatment which turns women into breast cancer TREATMENT survivors and does nothing to actually prevent the disease.

  3. ladyliza

    The chiropractor that does my thermographies had special training to read the results herself.

  4. fbl

    CH, why is Thermography NOT being offered as an alternative?
    Follow the money luv. It is all the big business side of medicine. The same reason that Homeopathy is ridiculed (but incredibly effective). Thermography is a lot cheaper and results in fewer biopsies. They can’t make the big bucks that way!
    Unfortunately my Thermography Doc. died and I no longer have that option-yet. I’m going to look for someone else locally. He had been a chiropractor and had diabetes that was tough to control. He died quickly of a heart attack.
    The equipment used to be dreadfully expensive but the last time I saw my Thermography Doc. he said that it was now available for $50,000. Hopefully more folks will pursue that field. It would be a great occupation for someone who has had radiology type experience. One has to be able to “read” the results.

  5. CH

    Why is it that thermography is not being offered as an alternative to mammograms?

  6. CMC

    My first and last mammogram was in the mid to late 70’s, I decided then to skip all tests unless I had a reason. No pap smears either. My way is to live a healthy life style. So far it is working. Will be 77 this year, and feeling great! Still work part time.

  7. ladyliza

    How come no one mentions vitamin C to prevent and treat breast cancer? There is plenty of research to back this up and 60 Minutes in New Zealand has a segment on You Tube that shows an example of one man’s miraculous return to a healthy life after being on death’s door. It works for several cancers and breast is one of them. The segment on TV was about swine flu and hairy leukemia, but I read about it long before this show. My doctor even offers intravenous vitamin C in his office for those who want it. It helps to boost the immunity during flu season.
    An acquaintance of mine is an oncologist who told me there are many herbs that are also curative for some cancer patients. So what I am saying, is there are things one can do to prevent or cure some cancers if we are willing to think outside the box of allopathic medicine. That means we have to do our own research and push the medical establishment to listen to our needs.

  8. HG

    In reference to dense breast tissue, a friend of mine with beautiful breasts felt a small lump. She had recently had a hysterectomy due to uterine fibroids which, when removed, had no malignancies in the tissue. She was put on estrogen to blunt the discomfort of having gone into menopause from one day to the next. She had a mammogram which was negative. She said she wanted a lumpectomy anyway.
    The doctor ridiculed her, but agreed to do a needle biopsy. It was also negative, but my friend persisted in demanding a lumpectomy. Again she was ridiculed, but they did the lumpectomy and the mass was malignant. They performed a mastectomy and removed all of her axial lymph nodes, assuring her that they were sure the cancer hadn’t spread. But when the lab test results came back, she was actually stage four with involvement of all her lymph nodes.
    For just under five years she was put on one chemo after another. She finally died from heart failure, perhaps caused by one of the chemos (methotrexate?). Had she lived a month longer she would have gone down statistically as ‘cured’!

  9. O.G.

    It’s a thought, but…she was free of the breast cancer (supposedly) and then the lung cancer cropped up a few months later. There has been other speculation about the role of x-ray treatment in causing lung cancer, so I lean in that direction. Just an layperson’s opinion, but for my part, I’d rather avoid as many x-rays as I can.

  10. Laurie M.

    Maybe your sister’s Breast Cancer in a sneaky way spread to her Lungs before/during the Breast Cancer treatment? Just a thought….

  11. MJW

    From the latest reports, it appears that with regular mammograms, the detection rate is higher but the survival rate is not. I haven’t had a mammogram in 30+ years, and have no intention of having one. If the survival rate is no better, why should I spend the last few years of my life in fear, dealing with chemotherapy, mastectomies, and other treatments? It’s just a choice about how one lives life.

  12. Paraman B

    Are there peer reviewed studies of the carcinogenic risk of mammograms?

  13. KMS

    The very important fact that most analysis of this study fails to emphasize, and sometimes even to mention, is that ALL of the women received annual breast exams by a person trained in breast examination. That fact is SO important.
    Failing to obtain EITHER a mammogram OR a breast exam would be an extremely unwise choice, yet that is probably one that many people may make. Not all physicians who prescribe mammograms routinely conduct breast exams.

  14. SalW

    I recently told my 38-year-old daughter that she would have to do her own investigation to decide for herself how she feels about mammograms; I would hope that she choses thermography. Just last week, my gynecologist again pleaded with me to get a mammogram because I have not had one for the last five years. All women must make their own difficult decision.
    At age 75, I have had a lot of radiation exposure. The studies I have reviewed state that mammograms use ionizing radiation at a relatively high dose which can contribute to the mutations that can lead to breast cancer. You can get as much radiation from one mammogram as you would from 1,000 chest X-rays. Mammography also compresses your breasts tightly, which can lead to a dangerous spread of cancerous cells, should they exist.
    For those of us who have had common skin cancers (I have had many basal cell), we may be at an increased risk of getting cancer again in life, according to a study published April 23, 2013, in the journal PLOS Medicine. The study found that women with nonmelanoma skin cancers (such as basal cell carcinoma or squamous cell carcinoma) were 26 percent more likely to later develop another form of cancer, compared with women who didn’t have these skin cancers. Results showed that people with nonmelanoma skin cancer were at an increased risk of developing the deadly skin cancer melanoma, and that women with nonmelanoma skin cancer were at increased risk of lung cancer and breast cancer, according to the study.
    Since 80 percent of breast lumps are non-cancerous, and 70 percent of breast cancers are found through breast exams, I will continue to do my own examination since the breast is highly sensitive to radiation. I also believe that my immune system is my best cancer weapon, especially by optimizing my vitamin D level and also by making good diet and lifestyle choices. I also will continue to minimize my exposure to mammograms and other sources of ionizing radiation.

  15. fbl

    The answer of course is NOT to get mammograms.
    The better choice is to get thermography. This system uses a heat sensitive camera to examine the breasts. After a negative biopsy I told my family Dr. that I was NOT going through that again. He called me and told be about thermography several months later. I had severe fibrocystic breasts and the mammograms were excruciatingly painful. My son and hubby couldn’t even hug me it was so bad. I travel four hours out of town every two years for the exam.
    Notice the past tense? My Dr. started my on liquid iodine and over several years the masses cleared from my breasts. I discovered Iodoral and took it in for him to look at and he said it was good and to take one a day. I have no problem with fibrocystic breasts today.
    Heat sensitive cameras are used to examine aircraft structures to show metal stress. The cameras now used for thermography are much more sophisticated and cheaper.

  16. LL

    I chose to get my first mammogram at 50 and will get them at most every other year. I absolutely think there is a radiation risk from getting x-rays on the same sensitive place every year from 40 on. I have to wonder how many breast cancers are caused from mammograms. If there is a family history or risk factor, I can see getting them regularly from 40 on because the most aggressive cancers occur in the younger age group. Otherwise, I think we need to be more cautious with this test.

  17. Carolyn

    I feel that a mammogram probably saved me from having to deal with a much-worse problem than I had when a small lump was found in Nov. 2002 as a result of a mammogram. My breast was large enough and dense enough to make it hard to find even after we knew where the lump was located. I never felt the lump, nor could any of my doctors.
    A lumpectomy and radiation treatments followed and I have never been sorry that I took that route. I have had follow-up mammograms every year and have remained cancer-free. I look forward to the day when there will be better diagnostic tools available and less disfiguring solutions to a cancer diagnosis.

  18. Dell

    In 1997, I was diagnosed with breast cancer. It was discovered in a mammiogram and had developed within the year since my previous mammiogram.
    I had surgery and chemo, and I have been cancer-free for the past 16 1/2 years.
    My mother died of breast cancer. She never had mammiograms, and, when her cancer was discovered, it had already matastisized. While she went through all of the treatments, it was simply too late. That is proof enough for me, and I nag my daughter to get a mammiogram every year.

  19. A. HILLMAN

    I have had breast cancer in one of my breasts and surgery, I would like to know if I should continue getting a mammogram every year? I’ve had one yearly since 2004.
    The results are negative every time. Thank goodness!
    You are at higher risk than most so we would encourage you to work closely with your physician to determine whether a yearly mammogram continues to make sense. We suspect that she will advise you to continue doing what you are doing.

  20. O. G.

    Sounds like a whole new radio program is taking shape here! I’ll watch for it.
    I believe my sister’s lung cancer was a direct result of the radiation treatment of her breast.

  21. Paraman B

    What about women who have cystic breasts? Is it still true that regular (at least annual) mammograms are wise because feeling a lump is so difficult? What does People’s Pharmacy think? Also,there is no mention here (and in most articles debating the efficacy of mammograms)of added carcinogenic risk from the mammogram radiation itself. Wondering what PP thinks about mammogram risk from radiation. Thanks.

  22. MW

    So young women don’t need to be screened regularly. My doctor told me after 65 I don’t need to be screened. Seems that’s when your risk increases — with age. Too many young women die of breast cancer. Until the researchers can positively state which cancers are dangerous and which will not spread/kill, women should ignore these frequently changing recommendations and have mammograms. If you are the one woman to die because you didn’t “need” screening, it’s not much consolation to you or your family. And the AMA won’t really care.

  23. M.S.P.

    The outcome of this study is not new evidence. I learned about this (from the results of similar studies) at least 20 years ago from other studies that were done but were not accepted by the powers that be, at that time. A reminder that breast cancer starts usually at least 10 years prior to any lumps or growths showing up whether it be through self-examination or mammorgraphy.
    Take care of yourself with a healthy diet and regular exercise and maintain a healthy body weight.

  24. PRW

    Excellent summary and analysis. Thank you.

  25. O.G.

    All I can say–to stoke the flames of debate with more anecdotal evidence–is that my older sister had her first mammogram in ages a few years ago. It showed a growth in one breast “so tiny that if you had come in last year we couldn’t have seen it.” She was treated with radiation therapy, followed by chemo, and came through it successfully. Within a year she had developed a particularly aggressive lung cancer, even though she had stopped smoking twenty years before.
    The lung cancer has metastasized, pressing on her brain although with (now palliative only) treatment she is spiritedly holding her own, despite difficulties with language and other cognitive functioning. Fortunately she has a great support group of friends out there in California, and a daughter who takes wonderful care of her.
    Having seen her go through what she has, even though I know sequence doesn’t prove causation, I wonder what would have happened had she not gotten the initial mammogram. Her experience has pushed me into the “forget mammograms” camp, and this study caps it.

  26. JP

    One day, in the far future, people will talk about the crazy things people did in this era. Subjecting your breasts to radiation in order to screen for cancer will be one of those things. I have asked my friends that run yearly to have their mammograms, if you develop a tumor the month after you have a mammogram, when are you going to find out about it? 11-12 months later?
    I’m not denying that the “medical industry” has not saved lives, but I’m not so sure they have saved as many as they like to think and I’m pretty sure there are lives lost as a direct result of the for profit medical industry we have. I’m more afraid of the health care system we have than I am of dying from cancer.

  27. Meris

    I live in Switzerland where there is systematic screening for breast cancer for women aged 50 to 70 every two years. The Swiss Medical Board (which is not the Swiss federal health authority) recently advised against this. It created a furor in Switzerland.
    I am one of the (rather few) women who has benefited from this program – a stage I breast cancer was detected in 2004 at age 57 and I am fine today.
    I believe that screening for women under age 50 is controversial and probably not necessary. I also believe women should act wisely and do what they believe is best – due to false positives and negatives, she should have second or third opinions before taking the next steps.
    We should all try to add more preventive measures to our lives, meaning eat healthily – organic, exercise, try to avoid endocrine disruptors in foods and products, and also exposure to electromagnetic radiation from cell phones, Wi-Fi and other wireless technologies.
    It is too bad that some trustworthy authority cannot provide definitive advice on the very confusing issue of mammograms and also do more to reduce the pollution in our environment.

  28. BS

    We need better screening tools as mammography seems to be limited in identifying cancers in people with dense breasts. At the very least the patient should be told that nothing was seen due to the density of her breasts and if she would choose to have more definitive testing it should be left up to the patient. More testing would seem reasonable if the patient would meet certain criteria such as menopausal, the mature woman, history of female cancers in the immediate family.
    I realize a more definitive tests are not pursued due to cost – on the flip side of that–what is it costing insurance companies to treat breast cancer? I would rather error on the side of false positives than false negatives. Currently being treated for breast cancer that was not identified with mammography till it reached 4-5 cm . I did the recommendations of yearly mammograms.
    Perhaps we should employ the accuracy of cancer sniffing dogs as they seem to have a better track record than our current diagnostic machines .

  29. MD

    Back in the ’80s my husband, working for a company based in Murray Hill, NJ – C.R.Bard, developed an ultrasound-type diagnostic machine for breast health. The patient would put on a tee-shirt and bend over into a warm saline solution submerging the breasts – there was no pain, no tissue injury, no embarrassment, nor false-positives from tissue distortion, no radiation, less costly. It was ready for market, but it never happened. Why?
    The doctors said “No. No, time to retrain staff, purchase new equipment, and develop a new storage system for records.” Another sad commentary on our doctors and priorities.

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