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The USPSTF recommendations for breast cancer screening: Not the final word

Preface: On issues such as this, I think it’s always good for me to emphasize my disclaimer, in particular:

Dr. Gorski must emphasize that the opinions expressed in his posts on Science-Based Medicine are his and his alone and that all writing for this blog is done on his own time and not in any capacity representing his place of employment. His views do not represent the opinions of his department, university, hospital, or cancer institute and should never be construed as such. Finally, his writings are meant as commentary only and are therefore not meant to be used as specific health care recommendations for individuals. Readers should consult their physicians for advice regarding specific health problems or issues that they might have.

Now, on to the post…

“Early detection saves lives.”

Remember how I started a post a year and a half ago starting out with just this statement? I did it because that is the default assumption and has been so for quite a while. It’s an eminently reasonable-sounding concept that just makes sense. As I pointed out a year and a half ago, though, the question of the benefits of the early detection of cancer is more complicated than you think. Indeed, I’ve written several posts since then on the topic of mammography and breast cancer, the most recent of which I posted a mere two weeks ago. As studies have been released and my thinking on screening for breast cancer has evolved, regular readers have had a front row seat. Through it all, I hope I’ve managed to convey some of the issues involved in screening for cancer and just how difficult they are. How to screen for breast cancer, at what age to begin screening, and how to balance the benefits, risks, and costs are controversial issues, and that controversy has bubbled up to the surface into the mainstream media and public consciousness over the last year or so.

This week, all I can say is, “Here we go again”; that is, between downing slugs of ibuprofen for the headaches some controversial new guidelines for breast cancer screening are causing many of us in the cancer field.

On Monday evening, the United States Preventative Services Task Force (USPSTF) released new recommendations for screening mammography, which it published in the Annals of Internal Medicine, that have, let me tell you, shaken my specialty to the core. I must admit I was surprised at the recommendations. No, I wasn’t surprised that recommendations to change the ages and intervals recommended for mammographic screening were released. I saw something like this coming based on a series of studies, some of which I’ve discussed right here on this very blog, such as a study suggesting that one in three mammographically detected breast cancers are overdiagnosed and that as many as one in five breast cancers may spontaneously regress, coupled with evaluations suggesting that the number of lives saved by mammography is not as great as previously thought, such as this Cochrane Review updated last year. What surprised me is how much of a departure from current mammography guidelines the USPSTF recommendations were and, even more so, that they were released this year. I hadn’t expected recommendations like this this soon. But I have to deal with them, and in doing so I might as well try to help SBM readers understand them too.

The first thing that women need to understand is that these recommendations are for asymptomatic women at average risk for breast cancer undergoing routine screening for breast cancer. They are most assuredly not for women judged to be at high risk due to genetic mutations, strong family history, or other factors resulting in an elevated risk for breast cancer. Neither are these guidelines for women who are not completely asymptomatic. If you’re a woman, particularly if you’re over 40 but not limited to women over 40, and have felt a lump, that lump needs to be evaluated by a physician. Period. Screening by definition is administering a test to an asymptomatic population. These recommendations should not be used as a reason to delay or forego the evaluation of masses or other breast abnormalities. I mention this point ad nauseam because I sometimes see confusion between screening and diagnostic mammography in discussions of this issue. Again, screening mammography is for asymptomatic women. Diagnostic mammography is for women with a lump or who have been found to have abnormalities on a screening examination.

The second thing that needs to be understood is that these recommendations do not usurp the current standard of care, although it may seem that way from how they have been portrayed in the press. The American Cancer Society and other cancer organizations have not adopted them. That being said, I do rather suspect that the USPSTF guidelines are the first shot in a battle that is likely to change how we screen for mammography. How much our guidelines will change, I doubt that we will know for quite some time. That always leaves the question of what to do in the meantime. For me, that is to adhere with the current standard of care, albeit with perhaps a bit more flexibility for younger women.

First, the discussion to follow will make a lot more sense if I mention right now that the USPSTF grades its levels of evidence using this grading scale:

USPSTFgrades

And ranks its level of certainty using this scale:

levelsofcertainty

And here are its recommendations summarized:

  • The USPSTF recommends against routine screening mammography in women aged 40 to 49 years. The decision to start regular, biennial screening mammography before the age of 50 years should be an individual one and take patient context into account, including the patient’s values regarding specific benefits and harms. (Grade: C recommendation.)
  • The USPSTF recommends biennial screening mammography for women aged 50 to 74 years. (Grade: B recommendation.)
  • The USPSTF concludes that the current evidence is insufficient to assess the additional benefits and harms of screening mammography in women 75 years or older. (Grade: I Statement.)
  • The USPSTF recommends against teaching breast self-examination (BSE). (Grade: D recommendation.)
  • The USPSTF concludes that the current evidence is insufficient to assess the additional benefits and harms of clinical breast examination (CBE) beyond screening mammography in women 40 years or older. (Grade: I Statement.)
  • The USPSTF concludes that the current evidence is insufficient to assess the additional benefits and harms of either digital mammography or magnetic resonance imaging (MRI) instead of film mammography as screening modalities for breast cancer. (Grade: I Statement.)

And the summary for patients states:

The USPSTF found fair evidence that women who have screening mammography die of breast cancer less frequently than women who do not have it, but the benefits minus harms are small for women aged 40 to 49 years. Benefits increase as women age and their risk for breast cancer increases. However, there are relatively few studies of mammography for women aged 75 years or older. The potential harms of mammography include anxiety, procedures, and costs due to false-positive results and receiving a diagnosis and treatment of cancer that never would have surfaced on its own within a woman’s natural life time. They found that the benefit of mammography every 2 years is nearly the same as that of doing it every year, but the harms are likely to be half as common. They found no evidence that self- or clinical examination reduces breast cancer death rates.

There are two bombshells here. The first is the recommendation against routine screening mammography in women between 40 and 49. That’s the change that’s caused all sorts of controversy. Almost as big a bombshell is the recommendation for screening every other year, rather than every year. Add these two together, and it’s a recipe for confusion and controversy among women. After all, we’ve been recommending for a long time that women undergo mammography beginning at age 40 and then every year thereafter, no ifs, ands, or buts. It was a simple message, easy to transmit to women, easy to understand, simple to promote, although I would point out that it was anything but easy to convince women to undergo regular screening. Fear that it will be harder to persuade women to undergo screening may well be part of the nearly universally negative reaction to the recommendation that I’ve seen thus far from advocacy groups such as the Susan J. Komen Foundation and the American Cancer Society. I can understand how these new recommendations could be profoundly confusing to women.

That’s why it’s important to understand on what evidence these recommendations are based. It might help if you go back and read a post I wrote a couple of weeks ago that discusses a review of the literature that urged a rethinking of screening mammography. In that article, it was estimated that, for women between the ages of 50 and 70, 838 women have to be screened for over 5,866 screening visits to sayve one life. It often shocks people to hear these sorts of numbers, but they are not beyond the pale for screening programs. More importantly, the USPSTF based its update of its 2002 recommendations on newer studies, including a study included in the same issue of the Annals of Internal Medicine that used several models to estimate breast cancer risk reduction using various screening paradigms, as well as newer randomized clinical trials, such as the Age Study and updated Gothenberg trial data. These models and results are consistent with randomized clinical trial results that indicate that there is a reduction in breast cancer mortality that results from beginning screening at 40 years but the reduction is “modest and less certain than mortality reductions observed from screening women aged 50 to 69 years.” By using data from randomized clinical trials, the USPSTF estimates that averting 1 death from breast cancer requires screening 1,904 women aged 40 to 49 years; 1,339 women aged 50 to 59 years; or 377 women aged 60 to 69 years. As described above, there was little difference in the benefits between screening every year versus screening every other year, but there were considerably more harms.

The USPSTF’s recommendation not to teach breast self-examination (BSE) is another point of controversy. Despite a lot of enthusiasm for the practice, Cochrane Reviews and other evidence have failed to find convincing evidence that routine regular BSE saves lives. I wish it were otherwise, but it appears not to be, even though there are compelling anecdotes out there of women who did find a lump on BSE and it turned out to be cancer. Unfortunately, overall, the evidence to support BSE is weak. On the other hand, even the Cochrane Collaboration, which I have in the past sometimes accused of methodolatry and “nihilism” with respect to screening concluded:

Some women will continue with breast self-examination or will wish to be taught the technique. We suggest that the lack of supporting evidence from the two major studies should be discussed with these women to enable them to make an informed decision. Women should, however, be aware of any breast changes. It is possible that increased breast awareness may have contributed to the decrease in mortality from breast cancer that has been noted in some countries. Women should, therefore, be encouraged to seek medical advice if they detect any change in their breasts that may be breast cancer.

Indeed, on a purely practical level, I see nothing wrong with women being taught to be aware of how their breasts normally feel and to bring to a physician’s attention any changes that concern them and still encourage that.

So what are the harms of screening? First, there are “unnecessary” biopsies. I used quotation marks because we don’t know that the biopsies were unnecessary except in retrospect because our imaging technology is not good enough to differentiate benign from malignant as well as we would like, with as many as 80% of biopsies being negative. Second, as I’ve discussed before, there is a significant rate of overdiagnosis. Overdiagnosis is the detection of tumors that would never lead to life-threatening disease over the lifetime of the woman. Overdiagnosis leads to overtreatment because, again, we can’t identify which of these diagnosed tumors will and won’t progress; so we have to treat them all. The question then becomes: What is the risk-benefit ratio of screening. For ages 40-49, the analysis of the results by the USPSTF showed a 15% reduction in breast cancer mortality, which was similar to the risk reduction for women aged 50-59 while the risk reduction was 32% for women aged 60-69 However, given the lower incidence of breast cancer in the younger age range and the higher chance of false positives and overdiagnosis, the absolute number of lives saved is much smaller and comes at a higher cost.

But enough of all these numbers. For one thing, the supporting articles in the Annals of Internal Medicine are rather poorly written (no doubt written by a committee) and make it hard to tease out the clear comparisons of the numbers of women potentially harmed. Rather, what I want to emphasize here is that these new recommendations are a classic example of what happens when the shades of gray that characterize the messy, difficult world of clinical research meet public health policy, where simple messages are needed in order to motivate public acceptance of a screening test. It’s also an example where reasonable researchers and physicians can look at exactly the same evidence for and against screening at different ages and come to different conclusions based on a balancing of the potential benefit versus the cost and potential harms. The USPSTF simply came down on a side more like how many European nations screen for breast cancer. How this all will play out is an open question, because how breast cancer screening ultimately evolves will depend upon how women undergoing screening and we as a society end up deciding how to balance the risks and benefits of screening. It will also be affected by advances in technology and our understanding of the biology of breast cancer. The only prediction I can make is that the standard of care for breast cancer screening will almost certainly change. I doubt it will change all the way to the USPSTF’s new guidelines, but likely it will move in that direction, although I cannot predict how far. In any case, it’s always messy when that happens and leads to blowback. For instance, a professional society to which I belong issued a highly embarrassing press release, a case study in the wrong way to respond to a new set of recommendations like those of the USPSTF. The worst part of this press release was this:

We believe these recommendations effectively turn back the clock to pre-mammography days by making the diagnosis of breast cancer occur only when the tumor is large enough to be felt on a physical exam. The Society will continue to advocate for routine annual mammography screening for all women beginning at age 40. Mammography screening reduces breast cancer mortality and saves lives.

By this standard, I suppose much of Europe is “pre-mammography,” given that many countries in Europe use guidelines for screening mammography very much like what the USPSTF recommended. Nothing in the guidelines even suggests going back to those days. Reasonable physicians and scientists can disagree over whether the new guidelines represent a defensible attempt to apply current evidence about screening mammography to public health policy, but demonizing the USPSTF’s recommendations with such inflammatory language is neither productive nor reasonable. If you’re going to argue against the new guidelines, at least try to argue the evidence and counter what the guidelines actually say, as the American Cancer Society did:

  • The USPSTF says that screening 1,339 women in their 50s to save one life makes screening worthwhile in that age group. Yet USPSTF also says screening 1,904 women ages 40 to 49 in order to save one life is not worthwhile. The American Cancer Society feels that in both cases, the lifesaving benefits of screening outweigh any potential harms. Surveys of women show that they are aware of these limitations, and also place high value on detecting breast cancer early.
  • With its new recommendations, the USPSTF is essentially telling women that mammography at age 40 to 49 saves lives; just not enough of them. The task force says screening women in their 40s would reduce their risk of death from breast cancer by 15 percent, just as it does for women in their 50s. But because women in their 40s are at lower risk of the disease than women 50 and above, the USPSTF says the actual number of lives saved is not enough to recommend widespread screening. The most recent data show us that approximately 17 percent of breast cancer deaths occurred in women who were diagnosed in their 40s, and 22 percent occurred in women diagnosed in their 50s. Breast cancer is a serious health problem facing adult women, and mammography is part of our solution beginning at age 40 for average risk women.

This is a far more reasonable and nuanced critique that encapsulates starkly what the issues are. In essence, the ACS agrees with the conclusions of the data used by the USPSTF to support its recommendations but disagrees with the value judgments behind its recommendations to back off on screening in women under 50 and to decrease screening frequency to every other year. However, even the ACS couldn’t resist a little holding back in that it didn’t mention the raw numbers of lives potentially saved in each age group. In any case, I think the response from the American Society of Clinical Oncology (ASCO, a society to which I also belong) was much better. It did what I support, namely defending the availability of mammography to women over 40, while suggesting a more personalized approach to screening that represents a reasonable compromise between current screening recommendations that encompasses what the USPSTF has recommended:

Today’s recommendations from the USPSTF recognize the value of mammography in reducing breast cancer deaths, affirm the importance of mammography among women aged 50 and older, and emphasize that mammography should be seriously considered in women 40 to 49 after assessment of the risks and benefits. It is therefore of concern that at present more than a third of women who are now recommended for screening are not getting regular mammograms. While the optimal scheduling of regular mammograms is being discussed by experts in the field, ASCO would not want to see any impediments to mammography screening for any woman age 40 and above.

From ASCO’s perspective, the critical message is that all women – beginning at age 40 — should speak with their doctors about mammography to understand the benefits and potential risks, and determine what is best for them.

And that’s what it’s really about. The patient and her physician collaboratively determining what is best for her. Indeed, the current recommendations of the USPSTF are no less arbitrarythan previous recommendations for screening. What they reflect are newer studies and a different analysis of the the risk-benefit ratio, in which the more modest benefits of routine mammography in women between ages 40-49 at average risk for breast cancer are judged not to be worth the potential harm caused. Others may look at the same data and decide that the benefits of screening mammography in this age range are worth the potential harms. Individual women may hear the same benefits and risks and decide differently for themselves. Neither view is clearly inherently “right” or “wrong,” and what I hope we should all be able to agree upon is that women should be aware of and understand as much as possible those tradeoffs regardless before deciding upon screening.

In the meantime, I’m not quite buying that these new recommendations are so clearly more “science-based” than the older recommendations when, as the ACS points out, the USPSTF arbitrarily decided that screening 1,300 women to save one life is an acceptable cost but screening 1,900 to save a life is not. I do, however, think that we health care professionals have probably not sufficiently described the potential harms that come from screening in the past, and the controversy surrounding these guidelines is that failure coming home to roost. As I’ve written before, I sincerely hope that better technology and the discovery of new biomarkers can decrease these high numbers by increasing the specificity of mammographic screening and, possibly, even allowing us to identify which mammographically detected tumors don’t need treatment. Indeed, to me, the one advance that could most reduce the potential for overtreatment of image-detected breast cancer would be molecular tests that would accurately allow us to identify accurately the subset of breast cancers that are unlikely ever to progress and threaten the life of the woman. Another advance would be better imaging technology that could more accurately distinguish cancer from non-cancer or achieve the same thing as mammography without compression or radiation, which could lead to greater acceptance of screening. Finally, better biomarkers and tests that allow us to assess more accurately a woman’s true risk of developing breast cancer would permit targeted recommendations tailored to a woman’s individual risk. All of these are being actively researched, some at my own institution, but until such technologies and tests are developed we are left with mammography. As imperfect as it is, it is the best screening tool we currently have.

In the meantime, the application of science-based medicine to screening asymptomatic people for disease cannot avoid becoming interwined with a parallel discussion of how to balance risks and benefits, as well as a discussion of values. In the case of breast cancer, starting at 40 appears only to modestly decrease the absolute number of lives lost from breast cancer but at a fairly high cost of overdiagnosis and overtreatment, while screening yearly only increases the detection of breast cancer marginally compared to screening every year, also at a high cost in terms of more biopsies and more overdiagnosis. Whether the cost is judged to be worth it or not has to be evaluated on two levels. First and foremost, what matters is the woman being screened, what she values, and what her tolerance is for paying the price of screening at an earlier age, such as a high risk for overdiagnosis, excessive biopsies, and overtreatment in order to detect cancer earlier versus a relatively low probability of avoiding death from breast cancer as a result of undergoing regular screening. The next level is the public health policy level, where we as a society have to decide what tradeoffs we’re willing to make to save a life that otherwise would have been lost to breast cancer. Although screening programs and recommendations should be based on the best science we currently have, deciding upon the actual cutoffs regarding who is and is not going to be recommended to undergo screening and how often women should be screened unavoidably involves value judgments by those being screened, physicians recommending screening, and society at large.

It is just those value judgments that are driving the debate spawned by the USPSTF recommendations, a debate that is too frequently acrimonious when it doesn’t have to be.

Posted in: Cancer, Diagnostic tests & procedures, Politics and Regulation, Public Health

Leave a Comment (50) ↓

50 thoughts on “The USPSTF recommendations for breast cancer screening: Not the final word

  1. Grinch says:

    What will you do in your practice?
    Also, I wonder what Dr. val Jones thinks about this (as I loved her limericks)?

  2. David Gorski says:

    Offer mammography at age 40 to women with an average risk of breast cancer while explaining the potential benefits and risks. My position at the moment is probably closest to ASCO’s take, but as I read more I’m guessing my views may well evolve.

    In actuality, though, this is much more of an issue for primary care doctors. By the time I see a patient, it’s usually because she has a lump or an abnormal mammogram anyway that needs to be evaluated further and possibly biopsied. Either that, or she already has a diagnosed cancer. I’m usually not the one ordering or recommending routine screening mammography testing.

  3. Software Engineer says:

    Today’s Diane Rehm show was illustrative:

    A group of doctors (some who are directors of breast cancer screening clinics) and their callers decided this was just misogyny.

    More alarming, Medical Ethicist Arthur Caplan not only agreed it was misogyny and that we all think women’s lives are worth less than men’s, but he also said that these changes were unethical.

    If eliminating/modifying tests/treatments that prove to be less effective, or even harmful due to overtreatment and false positives is unethical, well,

    I guess science based medicine is doomed from the get go.

    As always, all paths lead to Theodoric of York:

    “Theodoric of York: [ steps toward the camera ] Wait a minute. Perhaps she’s right. Perhaps I’ve been wrong to blindly follow the medical traditions and superstitions of past centuries. Maybe we barbers should test these assumptions analytically, through experimentation and a “scientific method”. Maybe this scientific method could be extended to other fields of learning: the natural sciences, art, architecture, navigation. Perhaps I could lead the way to a new age, an age of rebirth, a Renaissance! [ thinks for a minute ] Naaaaaahhh! “

  4. Grinch says:

    Thank you sir. I, as a GP, have the aforementioned dilemma. But I take it on a case-by-case basis. Also, this recommendation is counter-intuitive to the population, as a whole. This is because, IMHO, we have been inundated with the “pink blitzkrieg” (I don’t mean in a derogatory fashion). It’s pink this and pink that, my box of serial is pink! Even if the science is solid, the society has been so deluged with cancer awareness (I’m not saying that it’s a bad thing) that these recommendations will be tossed by the way-side and the authors mocked and I’m sure damned.

  5. David Gorski says:

    More alarming, Medical Ethicist Arthur Caplan not only agreed it was misogyny and that we all think women’s lives are worth less than men’s, but he also said that these changes were unethical.

    Really? I’d be surprised if that’s really what Caplan said. He’s usually far more nuanced than that about these issues.

    My guess is that, if he truly said that, he doesn’t truly understand the issues involved. Perhaps I’ll send him some of my posts on screening, lead time bias, length bias, overdiagnosis, etc. :-)

  6. Plonit says:

    Do you feel that asymptomatic women at average risk of breast cancer in countries that have a more conservative (publicly-funded) screening programme should pay privately for earlier or more frequent screening?

    e.g. NHS Breast Screening programme screens women age 50-70 (47-73 from 2012) every three years.

  7. patrickd says:

    An “unnecessary biopsy” is a biopsy into obviously malignant tissue. If you have reason to be suspicious, but still have some uncertainty, the biopsy is justified. The question, I suppose, is what constitutes justifiable grounds for suspicion. It seems to me that most of the controversy stems from the “harm” generated, or perceived to be generated by false-positive screenings. How to the researchers purport to be able to count the number of malignant tumors removed which never would have harmed the patient in the first place? Why does the study group need to estimate risk aversion for all women? Cannot they present their data as a sort of spreadsheet? Enter your age, and other appropriate demographic data, then some sort of quantification of the amount of “risk” you’d be willing to undergo – in each of the categories defined by the study group: anxiety, pain, potential of undergoing an “unnecessary” (i.e., negative) biopsy, potential of removal of a tumor that may spontaneously regress (SOMEONE seems to think they can quantify that one), etc. – to find a “bad” cancer, if one is present. Then, quick as you can say “Bayes,” up comes your personalized recommendation!

  8. Software Engineer says:

    Unfortunately there doesn’t seem to be a transcript or an mp3 of the drshow, and maybe there will be later, but yeah, I think my paraphrase is honest and accurate.

    Have to get my kids, but briefly, the basic point was that removing tests/treatments we have long relied on is unethical. I really could not understand that point. As I said, Theodoric of York-time.

    There was another point made that I did agree with, that politically, it would be difficult to remove these tests and treatments. But he went full “unethical.”

    Gotta go.

  9. David Gorski says:

    @patrickd

    Mammograms are ranked by radiologists according to the level of suspicion for malignancy according to the BIRADS scale, from 0 to 6. I paraphrase:

    0: Need more imaging
    1: Stone cold normal
    2: Not completely normal but benign
    3: Probably benign (in practice there is less than 1% chance of malignancy, and the standard recommendation is a six month followup study)
    4: Suspicious, biopsy recommended
    5: Very suspicious
    6: Known, biopsy-proven cancer.

    These rankings are based on several factors and this is a well-validated, albeit not precise, system. Most biopsies are done for category 4 mammograms, and only around 20-25% of those biopsies reveal cancer.

  10. Harriet Hall says:

    I’m not practicing any more, but I keep up with the CME from the American Academy of Family Physicians. According to what I have been reading there in recent years, my approach would have been to offer mammography to women over 40 with an explanation of the risks and benefits and let them participate in the decision. I would have made it clear that the risk/benefit equation for a 40 year old was different from that for a 50 year old, that risk factors like family history should be taken into account, and that a 2 year interval was recommended in Europe. And I would have stopped recommending breast self-exam several years ago, although I still would have advised women to promptly report any lumps or other changes they noticed. If I had been practicing that way, I don’t see that the new recommendations would have changed my practice.

  11. cmhmd says:

    I think Art Caplan’s comments were fairly characterized. I had a couple thoughts while listening to the DR Show and reading this excellent post (I linked to it from dailykos, crooks and liars and firedog lake):

    1. As TR Reid has pointed out, the British National Health Service knows that the population of Britain is their responsibility from the moment of conception until its last breath.

    They are responsible for paying for the screening, the prevention and the treatment for the disease, including surgery, chemotherapy, etc.

    If, as charged, this is all about saving money, why are their recommendations so similar to the new USPTF recommendations?

    2.I find an interesting juxtaposition when I read and hear about the flu vaccine and screening for breast cancer.

    It seems that the low risks of getting a flu vaccine are magnified to hysteria and the low, but present, risks of radiation exposure, anxiety, minimally invasive breast biopsies and full surgical tissue resections are minimized in an equal but opposite way.

    How do we reconcile these two tacks on these issues?

  12. bobsmith says:

    I’m curious what your take is on mammography induced cancer. The Nationals Academy of Sciences estimates that for a ten year period of screening, there will be 8 deaths for every 100,000 women who undergo screening every year. I found other information (http://seer.cancer.gov/statfacts/html/breast.html) that says the total rate of cancer deaths is 24.5 per 100,000 in the US, so 8 per 100,000 seems like a significant increase in the mortality rate. To me, that seemed like the most convincing evidence that we may be over screening for that age group.

  13. JerryM says:

    this change in policy was reported here in the Netherlands as falling in line with our own policy, so I was curious what the US perspective would be.

    But I guess we’re all mysoginist pigs over here.

  14. James Fox says:

    This discussion is quite interesting and all the more pertinent when those in opposition to science based evidence seem to be basing their arguments in ideology, tradition and beliefs but are not part of the regular opposition in the CAM/woo camp. Change happens and clearly in this situation where those sorting through the hard facts to make rational and workable best practice recommendations ended up surprising some people who have a significant emotional investment. And if the perception is that it’s about misogyny, then perhaps some practice recommendations should have been simultaneously announced regarding the efficacy of digital rectal prostate examinations.

  15. Val Jones says:

    Hi Grinch,

    Thanks for the high five on the Limericks. :) I liked David’s analysis, and I think that Harriet, Dave, and I all more-or-less agree on what we’d say to our patients. The way I see it, the key issue is:

    “The USPSTF arbitrarily decided that screening 1,300 women to save one life is an acceptable cost but screening 1,900 to save a life is not.”

    If someone could tell me what that works out to in cost/life years, it might help to bring some additional nuance to the value judgment USPSTF is making.

    To be honest, I think the difference between saving a life by screening 1,900 vs 1,300 is small enough to make me want to screen the 40-49 year olds. But I wouldn’t squirm if they wanted to opt out. My value judgment is that if a woman has a whif of increased risk, I’d encourage her to be screened in her 40s. If she truly has no risk factors – then I’d let her decide, and would be ok with forgoing screening till age 50.

    But boy will I be psyched when we have a better screening test – or figure out how to predict which tumors will progress and which will not. :)

  16. pmoran says:

    Whole population screening inevitably entails setting an arbitrary value on each life saved — how much is (someone) prepared to pay for it?

    Different countries and different payment systems will inevitably come up with different figures, and it should be no surprise that America has up to now had more liberal quidelines than anywhere else.

    Screening IS tricky, for many reasons, some of which David has mentioned. Harriet’s admirable instinct to involve the private patient in the decision-making will result in the most expensive and inefficient activity possible at all stages where decisions have to be made.

    That doesn’t mean that it is wrong, but that it is not really adhering to the principles that are needed for the cost-efficient screening of whole populations. It will require additional funds to be injected into the system from somewhere, either from the patient or other insurees. That is fine so long as we are not setting that approach up as the optimum for all systems and all patients.

    Even as a private surgeon susceptible to the same instincts as Harriet , I had to admit that publicly funded and run mammographic systems were the optimum if you wish to start up such a program. That applies in nearly all aspects: in quality control, especially in having expert and confident radiologists, in information gathering for future decision-making, in producing the lowest negative biopsy rates, as well as cost-efficency.

  17. gaiainc says:

    I do family medicine and I had at least three 15-20 minute conversations with women today about the USPSTF recommendations, breast cancers that regress, overscreening, self-breast exams, etc. This was not what I was expecting to do today, but sometimes that happens. What I heard the most from my patients was if their insurances were going to cover mammograms at age 40 or not. I advised that it was unlikely that any insurance coverage would have changed in the past two days and that likely if change was going to happen, it was going to happen in the next 1-5 years. This was one group’s recommendation and that there would be a lot of discussion about this.

    I do think that we are overscreening in the US and pulling back a little is not bad. It may also get my vice-chair from focusing so strongly on how we’re doing on mammogram screening (which is driving me crazy, but that’s another story for another time). At the end of the day, as with any screening recommendation, it comes down to a conversation between my patient and I about what she wants, what she’s willing to take as a risk, and what I’m willing to take as a risk as well. These are guidelines and have to be taken in the context of the individual.

    I agree with Dr. Jones that I’ll be pleased beyond all imaging if and when we get a better screen test or able to predict which tumors are trouble and which ones are not. I am not holding my breath about these coming any time soon. Maybe in 5-10 years. Maybe. We’ll see.

  18. micheleinmichigan says:

    Good Article Dr. Gorski. I found the juxtaposition of the USPSTF’s recommendations and rational and the American Cancer Society comments particularly helpful. I currently have a lab slip for a routine mammogram that my doctor ordered last week. If I’d know these new guidelines were going to come out, I would have had a conversation with her about if I have family risk, etc. If I am not high risk, I would just as soon go to every other year.

    I do wonder, I have a needle biopsy for thyroid nodules a few years ago (negative for cancer). Pain wise it was incidental. The worry wasn’t bad, but of course thyroid cancer has much lower mortality, so not as much worry. Is the breast lump biopsy a lot more intrusive (pain and risk wise)?

  19. storkdok says:

    This is a great post and discussion. I would also discuss and make the same recommendations that you and Harriet spelled out so nicely.

    It is interesting in that I have had several women talk to me about this since yesterday. They are shocked and irritated, and some are even very angry. I’m not surprised at the new recommendations, more that they are this soon and, IMHO, were not presented well to the public. I did like the ACS response.

    An interesting response on FB was that this might be some way of rationing care by the govt, because to some the discussion of “it’s not worth screening younger low risk women because of the risk/benefit ratio” turns into “we are not worth screening” or “the soon to be govt run health care doesn’t want to spend the money to screen and save a few of us”.

    And I do have to wonder how fast the insurance companies are going to jump onto this to not cover screening in women’s 40′s who are at low risk. There is already difficulty in getting mammograms covered.

  20. Zoe237 says:

    Good, well balanced article. From what I can tell, the USPSTF seems to be less guided by politics than some other organizations. I fully expected SBM to be on the side of doing more tests and against doing nothing for low risk women. Glad to know I was wrong and that this was a balanced, rather than fear based, assesment.

    I do wonder however what the big difference is between age 40 and 50, and why the line of demarcation between 1300 and 1900 lives saved (although, based on experience, I can’t believe the risk/benefit analysis is that simple).

  21. Harriet Hall says:

    Micheleinmichigan asked, “Is the breast lump biopsy a lot more intrusive (pain and risk wise)?”

    I can speak to that. This is an anecdote but hearing a personal experience may help to put a human face on the dilemma. I’m not the typical patient, because I have several risk factors for breast cancer. So I had more reason than the average woman to get screening mammography. I never had a lump, but twice I had mammograms with suspicious microcalcifications (at age 60 and 62). Both times they tried needle biopsy but it was inconclusive. Both times I ended up with excisional biopsies. That meant the operating room, an anesthesiologist, and a huge rigamarole – hospital admission, fasting, IVs, pre-op lab tests, EKG, followup appointments with the surgeon, etc. On the morning of surgery, I had to go to the mammography suite where they took a long time inserting a wire through a needle into the area of interest to guide the surgeon and confirmed its location with repeated x-rays. I went back to the surgical suite with a wire protruding from my breast and taped down so it wouldn’t shift. I was offered either general anesthesia or local with IV sedation. I refused the sedation and had the surgery with only a local anesthetic; that eliminated side effects like post-op grogginess and nausea, and it minimized my time in the recovery room. Afterwards, they had me keep pressure on the surgical site for a couple of days with two tightly fitting sports bras and ice packs. There was moderate discomfort but I didn’t need the pain pills they gave me. As with any surgery, there is a small risk of bleeding, infection, and complications of anesthesia. I was less worried than I think most women would be, because of my medical background and personality. I would guess most women would be highly anxious about the possibility of cancer, about the unfamiliar procedures, about gross things like a wire protruding from their breast, and about the delays and waiting for results.

    My biopsy results were benign. The second time it showed lobular carcinoma in situ, which apparently does not mean what I usually think of as carcinoma in situ, and is not considered to be “cancer.” Both times, the suspicious area was completely removed. No followup was recommended except for continuing annual mammograms and additional breast MRIs because of my high-risk status.

    I will never know whether the mammograms saved my life by removing an area that would have developed into cancer, or whether they were both false alarms resulting in considerable inconvenience, removal of normal tissue, and a permanent scar. I was personally glad to trade the risks and inconveniences of biopsy for the peace of mind, but I look back and wonder if I might not have been better off if I had never had a mammogram.

  22. storkdok says:

    Harriet, thank you for sharing your story. My mother underwent the same procedure a year ago. Her surgeon called us on Christmas Eve, she was visiting us right afterwards, to tell her the benign results, which greatly relieved her mind. He didn’t want her to go through her whole vacation and holiday with it weighing on her mind. I now wonder the same thing, as she is 75.

  23. micheleinmichigan says:

    Harriet Hall, Thank you for the personal account. I does sound more intrusive than my thyroid biopsy I’m glad not to be make a future decision based on a misperception.

    I was also happy with Dr. Gorski’s approach on self-exam. While I can see that routine, regimented training and execution of self exams could be scientifically ineffective, I have heard enough stories from women, who found a irregularity and thought “That doesn’t seem right” reported it to a doctor and found cancer. It is good that they are encouraged to consult their doctor.

    And now I’ll throw a little CAM story in (to delight or annoy but hopefully not derail). Many years ago my Grandma noticed a large new dimple in her breast. She showed it to her chiropractor. He gave her a salve to put on it. She followed his instructions for a year or more before getting concerned and showing it to my mom, who promptly flipped out (about the chiropractor) and called my Grandma’s doctor for an appointment. Luckily the cancer was slow growing and was not fatal. But my Grandma did need more extensive surgery and treatment than she might have if she had known to immediately go to the doctor.

    This wasn’t an intentional doctor avoidance on my Grandma’s part, she just didn’t have the appropriate knowledge. I hope that some emphasis on continuing to educate patients on reporting changes in the breast to a DOCTOR continues.

  24. David Gorski says:

    @pmoran

    Actually, I had a question I hoped you could clarify.

    My understanding is that Australia recommends biannual mammograms beginning at age 50 but will still pay for any woman between 40-49 who wants to start screening earlier. Leaving aside whether biannual exams are enough, which, as I said, is more a value judgment regarding benefits and risk, if that is true about Australia, it seesm as though Australia has a reasonable compromise.

  25. Plonit says:

    Reading an account of the UK NHS breast screening programme here -> http://www.cancerscreening.nhs.uk/breastscreen/publications/nhsbsp61.pdf

    I noticed the following statement “For women in England who are screened by the NHSBSP over a 10 year period using two view mammography, the risk of a radiation induced fatal breast cancer is estimated at 0.1 and 0.04 per 1000 women aged 50–59 and 60–69 years respectively (an average of 0.07 cancers per 1000 women screened at age 50–70).” (p. 34).

    Is this an argument for less frequent screening (i.e. reduced exposure) if the incidence of interval cancers is low?

  26. pmoran says:

    David. “My understanding is that Australia recommends biannual mammograms beginning at age 50 but will still pay for any woman between 40-49 who wants to start screening earlier. Leaving aside whether biannual exams are enough, which, as I said, is more a value judgment regarding benefits and risk, if that is true about Australia, it seesm as though Australia has a reasonable compromise.”

    The Australian public has free access to excellent Government-run “Breastscreen” centres, and that is indeed their policy.

    As I am sure you realise in relation to the 40-50 years age group, the issue is not simply that ” — screening 1,904 women ages 40 to 49 in order to save one life is not worthwhile”

    In these denser, perimenopausal breasts there are going to be a lot more uncertain findings and false positives, leading to unnecessary anxiety, more tests and repeated tests and more invasive diagnostic procedures, blowing out the costs of screening this group disproportionately. Then there is the considerably greater risk of false negatives, women told they don’t have cancer when they do.

    There is no right answer, it is a matter of arriving at the right balance.

  27. DrDownUnder says:

    I think we do have a reasonable compromise here in Australia, and the switch to digital mammography is nearly complete for all of the BreastScreen centres. Women in the target age group (50-69) are also sent reminders to schedule their bi-yearly mammogram after they’ve attended for their first one. Our mortality rates from breast cancer are pretty equivalent to the US. We also promote “breast awareness” as opposed to self-examination, and have had tv commercials about it…

    A few months back, though, there was some controversy and discussion about whether BreastScreen should be available for women in their 40s or whether resources should be targeted towards getting more women in the target age group to get their mammograms. This came about partly because of the “Kylie Minogue” effect – when she was diagnosed with breast cancer a whole bunch of women in their 40s suddenly showed up at BreastScreen!

    We also do pap smears every two years, and may move to three after two normal exams in a row.

  28. DrDownUnder says:

    Sorry, I meant every other year, not bi-yearly mammograms!

  29. halincoh says:

    “Although screening programs and recommendations should be based on the best science we currently have, deciding upon the actual cutoffs regarding who is and is not going to be recommended to undergo screening and how often women should be screened unavoidably involves value judgments by those being screened, physicians recommending screening, and society at large.”

    Unfortunately, insurance companies do not prefer individual value judgements, they prefer rigidity ; they prefer prior authorizations if a value judgement is to be made.

    As a primary care doc I’m waiting to accumulate as much commentary and data before I change what I do, if I change what I do. At this present time it does seem like one size does not fit all. Rarely does it ever. This post is a great beginning. Thank you David.

    But … insurance companies , unless there is a great push from medical organizations with a vested interest, will embrace a more exclusionary approach and push the burden of proof onto the physician. Less mammograms will be done than needed if a prior authorization is needed.

    We physicians must fight for the option to act in the best interest of our patients WITHOUT jumping through hoops. Because hoops deter. And insurance companies LOVE hoops.

  30. KA says:

    Thanks for the informative post. Two questions. You briefly mention European practices (where, if I understand correctly, most countries recommend screening after age 50), but you don’t report any incidence stats or outcomes data resulting from this. Where incidence is comparable, the difference in practices should give us one more data point to evaluate. I understand why comparative data would need to come from controlled studies. Have there been such studies? In the absence of these, what might informal comparisons suggest? My second question is, what is the basis for relating studies and recommendations to the decade numbers, 40-49, 50-59, etc.? There ought to be enough data to give more specific breakdowns, e,g,. risks/benefits associated with ages 43.6-47.1, 47.2-55.45. Is this an example of science following popular culture in its testing of categories? or is it a consequence of having to translate the message into easy marketing lingo (i.e., you can’t say the number 55.45 in an ad about screening)?

  31. art malernee dvm says:

    The second time it showed lobular carcinoma in situ, which apparently does not mean what I usually think of as carcinoma in situ, and is not considered to be “cancer.”>>>>>>

    I see HH used the word “apparently”. What do i tell my client now when the biopsy of the breast lump on fido comes back lobular carcinoma?

    The other comment others made that confuses me was about saving lives.

    >>>I do wonder however what the big difference is between age 40 and 50, and why the line of demarcation between 1300 and 1900 lives saved (although, based on experience, I can’t believe the risk/benefit analysis is that simple).<<<

    Doesn't the data shows between 40-50yrs a decrease risk of dying from breast cancer but no decrease in quality of life or no decrease in life expectancy. If your quality of life is not improved or the prevention does not increase life expectancy why not spend your money on something else we know that does?

    art malernee dvm

  32. Keith says:

    Software Engineer: “More alarming, Medical Ethicist Arthur Caplan [on the Diane Rehm show] not only agreed it [the panel recommendation] was misogyny and that we all think women’s lives are worth less than men’s, but he also said that these changes were unethical.”

    This is probably a mischaracterization of what Caplan said. His ultimate concern was that, although these recommendations were based on valid science, that any recommendation change involving retraction of benefits will be politically challenging and perhaps not worth it.

    His point about misogyny was NOT specifically about these recommendations. Rather he stepped back and admitted to a caller that HISTORICALLY medicine has not always valued women’s lives as much as men’s. He cited the treatment of heart disease as his example. In so doing he was trying to empathize with a caller’s skepticism in these recommendations, rather than to discard her concern as illegitimate. What he then failed to do, however, was make a comment on whether he believes these recommendations were or were not guided by misogyny, which probably left room for interpretation.

    ——-
    Dr Gorski – great post, very informative. Thanks!

  33. David Gorski says:

    Actually, I had a brief e-mail exchange with Dr. Caplan, and Keith’s characterization is much closer to what Caplan said. He also wrote an op-ed in which he clarified his position:

    http://www.msnbc.msn.com/id/34040273/ns/health-cancer/

    Actually, I find his thinking a bit muddled in this article. Maybe I’ll explain why sometime.

  34. tcw says:

    If for the last ten years we said “get your colonoscopy at age 40″ and now just changed it to age 50, would there be as much chatter and accusations?

  35. Harriet Hall says:

    Colonoscopy apparently reduces the risk of colon cancer death from cancers in the left colon, but surprisingly it has no effect on the death rate from cancers in the right colon.

    By one estimate, screening 1173 patients with FOBT [fecal occult blood testing] for 10 years will prevent one death from colon cancer. No studies have directly compared colonoscopy with FOBT, and we have no direct evidence (i.e. from randomized controlled trials) that any colon cancer screening test reduces total all-cause mortality.

  36. JMB says:

    There is no scientific basis for deciding that 1 in 1904 is unacceptable, and 1 in 1330 is acceptable.

    The decision about what is acceptable is made by placing a value on the number of lives saved, versus the cost of doing more exams (cost being either dollars, or discomfort and anxiety). Although the decision by the USPSTF is enshrouded in the process of computer simulation and efficient frontier analysis, it is still a value judgment, not a scientific observation.

    We all need to be careful about what is scientifically based medicine, versus decisions made by placing value on discomfort and anxiety, or simply cost-effectiveness. A value judgment made by a scientist is still a value judgment.

    The scientific observations can tell us that more lives will be saved if women are screened between age 40 and 50 (lives saved outnumbering lives lost due to complications from treatment or radiation exposure). The computer models can give us an estimate of the number of women that have to be screened to save 1 life. However, the value judgment of harm of discomfort and anxiety versus a small chance of saving your life is normally left to the individual patient to decide. Whatever the loss of life due to treatment complications of overdiagnosed or overtreated cancers, radiation induced cancers… the patient will have greater benefit from the screening process. That is the science. If you wear a seatbelt when traveling in a car, you might die from being trapped in the burning vehicle if a wreck occurs. However, the evidence indicates you are more likely to benefit from wearing the seatbelt in the event of an accident. Computer models based on scientific evidence suggest that for every life lost due to radiation induced breast cancer, we save 50 to 150 people.

    It is perfectly reasonable for an informed patient to decide against participating in a regimen of screening for breast cancer when she is properly informed. But it would be incorrect to tell them that there is no scientific evidence to support the recommendation that screening begin at age 40, and be performed on an annual basis. The proper information is that the most effective screening strategy for preventing a breast cancer death is yearly mammography from age 40 to 79 (as derived from the computer models in the USPSTF evidence synthesis articles). However, there is discomfort and anxiety from the exam and possible biopsies, as well as possible identification of tumors that may have not been significant. Furthermore, (and this is what the USPSTF emphasizes) only a small percentage of women will actually benefit. The likelyhood of having an unnecessary biopsy (or call back) is significantly reduced if screening is done on a biennial schedule beginning at age 50. However, some of the cancers will have progressed more (and more will die from the breast cancer). Then the patient can make a value judgment.

    It would not be true to tell the patient that scientific evidence does not show a greater benefit to screening mammography on an annual basis from age 40 to 79, than the strategy of biennial screening from age 50 to 75.

    The USPSTF makes a distinction between the most ‘effective’ screening strategy (the most years of life saved), and the most ‘efficient’ screening strategy (based on efficient frontier analysis from Modern Portfolio Theory in economics). They based their recommendations on the most efficient strategy.

    If you multiply 1 in 1900 times 22 million women aged 40 to 50 in the United States, you will come up with an estimate of the total number of lives we might potentially save (in a ten year interval). If you use the computer models, you can show how many lives can potentially be saved by using the most effective strategy (hint… thousands every year). Although in the real world, few women adhere to the yearly strategy, enough do that a difference in population statistics can be observed between the US an western Europe. We have a lower breast cancer mortality.

    Science based medicine should have a clear vision of what is science, and what is decision analysis. If decision analysis sticks to Bayes analysis (or stochastic formulations), it is still properly called science. The most effective screening strategy can be determined by science. If decision analysis incorporates a utility function (such as where the slope of the efficient frontier function levels out), it has introduced a value judgment. The most efficient screening strategy places a value on reducing the number of screening exams (the USPSTF states that the value of reducing screening exams is to reduce discomfort and anxiety, and also notes that the number of exams serves as a proxy for the cost of screening).

    In response to one question I saw posted, just do a search for ‘cancer survivabilty statistics by country’. The US leads the world in breast cancer survivability. Another interesting search is ‘risk of dying web tool’. They allow you to compare risk of dying from various causes. Although I have not been able to get the tool to give me the result, one reported result is that a 55 year old woman in the United Kingdom is 33% more likely to die from breast cancer than a similar women in the United States. Breast cancer in younger women tends to be faster growing (supporting the idea that we should be screening on a yearly schedule), but younger women tend to live longer before dying from the cancer. Women dying at age 55 would possibly have had early detection in the age group 40 to 50.

  37. JMB says:

    Many doctors will also claim that women with breast cancer live longer after screening detection just because of lead bias. The randomized clinical trials with extended followup are specifically designed to eliminate lead bias. When the trials report a reduction in total breast cancer mortality between the no screening and the screening group after 10 or more years of followup, that eliminates lead bias (and overdiagnosis) affecting the outcome. Population statistics of breast cancer mortality reduction over all age groups confirm that we are saving more lives than inducing fatal breast cancers by radiation from mammography.

    I would fear a possible measurable increase in breast cancer prevalence in 10 to 20 years due to radiation from overuse of CT scans for diagnosis of pulmonary emboli and abdominal pain.

  38. rork says:

    Too late to get answers probably, but an interesting point for me that’s not directly addressed much was made by “art malernee dvm” noting that overall mortality is not changed in some studies – perhaps it has not been shown to change in any study of mammography. That is, when people say “838 women have to be screened for over 5,866 screening visits to save one life”, or “screening 1,904 women ages 40 to 49 in order to save one life” they are not adding that they only mean life saved from death by breast cancer. That is, I think that both of the quoted phrases omit “from death by breast cancer”, when to be correct that phrase needs including. So my first question is whether that is correct. If so, the statements might be overly optimistic.

    If so, there’s something that might be done before we think it is just about the costs or just a value judgment. We need to estimate how many people are being killed by a screening program. We hopefully are saving more people than we are killing, but that is not usually being demonstrated, right? We could test overall mortality. My guess is that no studies are sufficiently powered to detect the benefit of screenings if you try to do it this way, even though breast cancer death isn’t that rare. Is statistical power the problem? I hope it is that rather than that the screening benefit is nearly zero.

    I’ve seen folks scoff at the downside of screening and overdiagnosis merely being “stress”, which they deem as nothing compared to breast cancer death. Fair enough. But perhaps we are not being imaginative enough to think of ways we might be killing people.
    1) As noted by JMB, we might be giving people cancers that arise much later, due to the screening itself. Maybe there is some excess of effects similar to “escape from dormancy” due to unneeded biopsy too, I might further rashly speculate. Maybe the follow up times in these studies are not enough to catch those effects.
    2) Just showing up for the screening, and any unneeded followups, including unneeded surgery and following drugs, are expected to kill a few people (both patients, and innocent bystanders), just thanks to infections obtained getting to and at our medical centers, or medical errors. These are not breast cancer deaths.
    3) We may be killing some in stupid stuff like additional car accidents getting to all these screening and unneeded follow up appointments, especially if they are distressed.

    We might argue that those risks, or others I don’t list (suicide) are tiny, but they don’t need to be that great to get us a sum of 1/1900. Maybe part of the (secret) conclusion is that people do worry about this, and maybe the numbers like 1/1900 vs 1/1300 is getting into the range of the number of people we might be killing by the screening and overdiagnosis.
    I certainly do see that we might not want to talk about killing people very much in public, and should come up with prettier or fuzzier terms for it.

    Note that none of my worrying depends on the costs of the procedures, or costing out (loss function) of the unneeded disfigurement, drugs, etc. It’s just counting deaths (actually person-years), and you could adjust that for quality of life if you’d like. We still need to face the even more difficult tasks of costing it out – I’m not saying that has gone away. But it would be nice if we were confident in just the life and death stuff first.

    Straighten me out or point me to help and I will thank you.

  39. JMB says:

    In answer to the question about phrasing of lives saved, we could simply say that screening mammography will reduce breast cancer deaths. To be more correct and exact based on the design of the randomized clinical trials we could phrase the scientific evidence as follows. Take all of the women in the United States between ages 39 and 69, divide them into two groups, tell one group they are invited to have screening mammography, tell the other group to not have screening mammography. After 10 to 20 years, there will be more women alive in the group invited for screening mammography. Any deaths due to treatment and radiation, or psychological stress, or traffic accidents are counted just the same as those due to breast cancer (some trials will exclude accidents).

    In answer to the question about radiation exposure, a cat scan of the abdomen and pelvis or chest has about 100 times more radiation than a mammogram. If you have two or more of those cat scans in one year, you can begin to identify a small percentage increase in cancer. Radiation exposure from a mammogram is about equal to the amount of radiation received from the sun and the earth in 3 months. If you are going to be concerned about this amount of radiation, you should not live at higher elevations (like Denver), should avoid air travel, and avoid all cigarette smoke.

    In answer to the cost effectiveness, the USPSTF includes the traditional measures of cost effectiveness in one of the appendicies of the supporting evidence articles. The traditional measure of cost effectivness is the dollar cost per year of life saved (or quality-adjusted life years, QALY). For the screening strategy of annual screening beginning at age 40, it is estimated to be slightly less than $50000 per QALY. There are other screening and treatment programs funded by congress that are much more expensive than $50000 per QALY.

    A note about overdiagnosis and disfigurement. Over diagnosis usually is defined by the greater number of cancers found in the screening group than in the control group. That is estimated to be between 1 and 10%. (It is not considered a radiation effect because it is usually measured after 5 years. Cancers induced by radiation usually take at least 10 years to become apparent.) Overdiagnosis increases as women become older, because they are more likely to die before the cancer becomes noticeable. Overdiagnosis is more of a problem in women over 70 than in women under 60. Disfigurement due to surgery or radiation is not covered in the design of the 8 randomized clinical trials. However, with screening, the cancers identified are significantly smaller. Therefore more women can choose the option of breast conserving treatment as opposed to mastectomy. Studies that have evaluated that have included that as a justification of screening mammography (it also costs less). On average about 95% of the breast cancers that can be detected by screening mammography would have eventually been detected by feeling the lump after it grows larger. Because of the more advanced cancer found without the benefit of early detection, the woman would then need more expensive and disfiguring treatment.

    The point about discomfort and stress is that no one is better at judging the discomfort and stress than the patient. You don’t need a scientist to make that decision for the patient. It is not that we ignore the patients’ stress and discomfort. It is simply a decision made best by the patient. Respect the patient’s rights.

    In response to the observation that some trials do not show a reduction in mortality the following is the information from the USPSTF. 8 large scale trials were judged to pass the criteria designed to evaluate for the soundness of the design of the trial. Of the 8 trials, one showed more deaths in the screening group. two showed virtually no difference, and 5 showed fewer deaths in the screening group. When you add all of the 8 studies together (a simplification of the process of meta-analysis), you end up with a statistically significant reduction of deaths in the screening group versus the customary care group. That again is counting the number of deaths due to surgery, chemotherapy, radiation, suicide, etc. That holds true in the age group from 39 to 69. The only trial of the 8 completed in the United States showed a reduction in mortality in the group assigned to screening. The Canadian trial was notable for the poor quality of mammography. At one meeting I attended, a speaker said 7 prominent mammographers refused to participate in the study after seeing the quality of mammography. When one of them offered to go out and train the facilities how to do the mammography correctly, he was declined. The mammography quality in Canada has significantly improved since that time, as it has improved in all developed countries.

    Therefore, when large scale randomized trials show a statistically significant difference in reductions of breast cancer deaths due to screening, they are including the deaths that may occur due to surgery, chemotherapy, suicides, and traffic accidents (some designs will exclude accidents).

    A good comparison is the decision to wear seat belts. If you decide to wear a seat belt while driving, there is a small chance that you will die from being trapped in the car. There is a much greater chance you will be saved by wearing the seat belt. A woman between 40 and 50 is more likely to be saved by having a screening mammogram than by wearing a seat belt. The same woman is less likely to die as a result of having a screening mammogram, than dying as a result of being trapped in a car by a seat belt. That statement is hard to prove, but a woman is more likely to die from breast cancer between the ages of 40 and 60 than a traffic accident. Any traffic accident in which there is a fire or submerging the car in water is a potential source of death due to wearing a seat belt. One published estimate is that between 50 and 150 cancers are detected early by screening mammography, for every cancer induced by the radiation exposure. The percentage of fatal traffic accidents involving a fire or submerged vehicle is higher than that.

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