Last week's medical news centered on a New England Journal of Medicine (NEJM) article on breast cancer screening by mammography. The paper, authored by an international group of epidemiologists and biostatisticians, suggests that mammography has only a small influence on survival. The findings, along with an accompanying editorial, got front-page attention like this in the New York Times:
"...it indicates that improved treatments with hormonal therapy and other targeted drugs may have, in a way, washed out most of mammography's benefits by making it less important to find cancers when they are too small to feel."
But I'd say the opposite is true: It's precisely because there are effective treatments for early-stage disease that it's worth finding breast cancer early. Otherwise, what would be the point?
Mortality in the U.S. from breast cancer has declined by roughly a third since the implementation of wide-spread mammography screening around 1990. Despite so many advances in treating early-stage disease, the survival rate at five years for women with advanced tumors is only 25 percent. Metastatic breast cancer is quite costly to treat and remains incurable, even with treatments including new, expensive targeted therapies.
The new report:
The investigators looked at trends in breast cancer diagnosis and mortality in Norway over time after dividing the country into two sets of counties based on when a national screening program - which included mammography every other year for women between the ages of 50 and 69 - was implemented. The plan, which started in 1996 and required that each region establish a centralized, multidisciplinary breast cancer care team prior to participating, gradually expanded to include all of Norway by 2005. According to the study's authors, all Norwegian women between the ages of 50 and 69 years have been asked to participate in screening mammography since 2005; 77 percent have done so; Norway's nationwide cancer registry is nearly 100 percent complete. They evaluated a total of 40,075 women ("subjects") who received a diagnosis of BC between 1986 and 2005.
The main finding was that for women between the ages of 50 and 69, deaths from breast cancer fell from 25.3 to 18.1 (per 100,000 person-years) in counties where the mammography program was implemented around 1996. In counties where mammography was not covered until very recently, deaths from breast cancer also dropped: from 26.0 to 21.2 (per 100,000 person-years). Because breast cancer-associated deaths declined in all regions, regardless of whether mammography was offered, the authors concluded that screening doesn't account for most of the improvement.
By the authors' calculations, mammography accounts for roughly 10 percent of the enhanced survival since 1986. (This finding was not statistically significant.) They suggest that recent progress comes, for the most part, from better care and treatment of patients with this disease.
1. The average follow-up was only 2.2 years after diagnosis, with a maximum follow-up of 8.9 years. This is far too short an interval to measure the benefit of any sort of intervention in women who have breast cancer. When this disease recurs it's often after several years and, occasionally, decades after the initial diagnosis.
2. Among women under the age of 50 there was a slight increase in breast cancer deaths: A non-significant relative increase in mortality, of 4 percent, after the introduction of the screening program for older women. This worrisome finding is not adequately addressed by the authors. One might wonder: did fewer women in their forties go for mammograms after 1996, since they were only recommended and covered for older women? My question is whether reduced screening, now, among younger women is leading to an increase in breast cancer deaths.
3. Digital mammography was not evaluated in this study.
4. The authors detected the largest benefit of screening among women with Stage II breast cancer; there was a "marked" 29 percent reduction in mortality in that group relative to their historical counterparts, as compared to only a 7 percent reduction in mortality for women with Stage II tumors in areas where screening was not available. This observation suggests that mammography screening was life-saving for women with Stage II tumors. As an oncologist, I find this highly-plausible; the purpose of mammography is to identify tumors in early stage and spare women morbidity and mortality associated from advanced disease.
5. We should keep in mind the absolute number of lives saved in assessing mammography's value. Here, if the paper's conclusion is true -- that mammography reduces breast cancer deaths by just 10 percent, then in Norway -- with a total population of 4.8 million and 4,791 women who died in this study of breast cancer -- these results support that mammography spared approximately 480 lives over 20 years.
In the U.S., where some 45,000 women die each year of breast cancer, we'd save approximately 4500 lives per year if the added value of mammography is only 10 percent. If the benefit of screening mammography is higher -- say in the range of 45 percent, as was supported by a 2007 paper, also published in the NEJM -- then the value would exceed 20,000 women's lives per year. If the benefit is only 25 percent in terms of reduced mortality, that would result in over 11,000 lives saved, per year in the U.S.
My conclusions:
While the precise value of breast cancer screening by mammography remains uncertain, the recent paper confirms the marked progress in overall survival trends among women who have breast cancer. The question, really, is how much population-based screening helps women who are younger than 50, between the ages of 50 and 69, and older. Last week's publication was well-organized and carefully done, but it fell far too short in terms of follow-up to measure the potential impact of mammography on survival after breast cancer.
The Annals papers, which caused so much controversy last year, relied heavily on old data and did not at attempt to examine the efficacy of digital mammograms. What's needed, still, for public health policy in the U.S. is data regarding long-term outcomes after digital mammography performed in FDA-regulated, modern facilities by skilled, board-certified radiologists in the context of current pathology methods, decision tools and treatments.
As we espouse evidence-based medicine - which in principle should be cost-saving and spare patients from morbidity and mortality due to suboptimal care - we need think critically, more than ever before, about the limitations of medical knowledge and potential pitfalls in what's called "evidence."
Follow Dr. Elaine Schattner on Twitter: www.twitter.com/medicallessons
Samuel S. Epstein: Breast Cancer Unawareness Month: Rethinking Mammograms
~ Dr. Theresa Ramsey, Author of Healing 101: A Guide to Creating the Foundation for Complete Wellness, http://www.DrRamsey.com, @DrRamsey
Here is a question for those over fifty to ponder: Is it better to die at 65 of breast cancer at home or at 85 in a nursing home of dementia or pneumonia? Pardon my cynicism, but there is no good outcome.
I am still not sure that multiple mammograms don't contribute to developing cancer. I would much prefer the ultrasound approach, which at least isn't using x rays. I had 2 done in the Spring and they want me back again for another this fall. Why? To be sure, they say. So I will get 3 times the radiation they say is safe. And then I go to the dentist for that radiation, and what if I need an MRI for my arthritis in my neck? It all adds up.
The studies need to give ALL the relevant information and compare apples to apples. Also, record the women's diets, exercise routines, and other relevant information. They lump too much together in these studies.
Not one single mammogram that she took ever showed any of these tumors at any point. Only x-rays and surgery helped.
It was an obgyn during a routine manual exam that made the first discovery.
She knwo has it on her chart NO MAMMOGRAMS.
~ Caroline Sutherland, Author, The Body Knows, http://www.CarolineSutherland.com, @TheBodyKnows
i put a tight body suit on on,
and feel my breasts and under my arms..
i don't trust doctors.
In both Denmark and Canada large population studies since 2005 have revealed that in women taking regular mammograms and women who have never had mammograms the death rates from breast cancer were exactly the same.
Age of the female being screened is significant, for example the ten-year trial quoted in the December 2006 Lancet which concluded that, where pre-menopausal women went for annual breast cancer screening, there was no significant reduction in breast cancer mortality – across the 160,000 women tested.
The low doses of radiation associated with annual screening mammography could be placing high-risk women in even more jeopardy of developing breast cancer, particularly if they start screening at a young age or have frequent exposure, according to new research presented here at the Radiological Society of North America 95th Scientific Assembly and Annual Meeting.
Ever hear of the "inverse-square law"? Basically, a radiation source half as close to you gives you four times the exposure? Which is why cell phones probably do cause cancer, because we hold them right against our heads. Like a mammogram, radiation right near your body, billions of times stronger than distant gamma rays.
My basis for this knowledge is I majored in Physics and worked 5 years as a medical imaging consultant and programmer, attended RSNA, consulted with radiologists. Yours?
A model compared the risk of increased breast cancer mortality from mammography radiation to the mortality benefit from mammogram screening, using data from studies of women with comparable radiation exposure and estimates extrapolated from a risk model. Screening was associated with a net positive benefit when the following assumptions were modeled: screening effectiveness at least 10 percent and onset of screening at age 40 or later; the positive effect increased for women who begin screening at an older age, and for women with a family history of breast cancer. Screening was associated with a net negative effect for average-risk women younger than age 40, both because younger women are more sensitive to radiation and have a lower incidence of breast cancer. The assumptions used in this model may not be applicable to women with BRCA1 or BRCA2 mutations.
In sum, radiation risk from mammography is low enough that a screening mammogram program for average risk women over age 40 saves lives.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2361593/?tool=pubmed
BTW I worked many as a medical imaging programmer and consultant, manned booths at RSNA for many years, consulted with radiologists in US and EU. France spends 9% of GDP, has better health and longevity, we spend 17%. That's the result of the profession you are going into, most likely for the money. "Denial is not just a river in Egypt", so of course you believe your industry does good.
Every single breast cancer survivor in my group - 10-19 years out, have gotten yearly mammograms, whose cancers were discovered through mammograms (and back 10 years the machines were quite different) and we all discuss articles that intelectualize and vilify mammograms and the disservice to women the net result being further fear and confusion, and harm. By the way, some in the group had a reoccurence - also picked up by mammograms.
To all you women out there reading this bilge, get your mammograms - it saves lives..maybe even yours.
Actually it's true.
I will bet you have zero hours of study or training in imaging or radiation protection.
It's an easy calculation: take existing tests and figure what percent of disease they cure or prevent. I believe that number is less than 17%. So, as we add more tests, we will spend 100% of GDP on health care before we cure all disease.
Health care spending in the US now has negative results. That 17% of GDP is better spent on nutrition, housing, lots of things that would save more lives and extend longevity. Not to mention, make life worth living.
I'm certainly not against paying for mammograms, but all treatments must be cost-effective. At some point we will not be able to pay for diagnoses or drugs that help 1 in a 1000 people. We will have to become "death panels". We cannot afford to pay for procedures given to everyone, that only help a tiny fraction.
Checkups and screening are early-detection, not prevention. In no way do screenings and tests make you healthier. In fact, just the opposite: mammograms expose you to radiation, colonoscopies cause rectal tears requiring minor surgery in 1 out of 100 cases, etc.
The only preventative medicine doctors practice is prescription drugs that try to prevent disease caused by poor lifestyle and diet. And those don't work, for example researchers in BC showed that statins do not reduce hospitalizations or deaths; they don't even save lives, never mind money.
I agree with you on diet, we could save billions if we ate different. But doctors don't advice their patients on diet or even being overweight. I have a friend who is taking an anti-diabetes drug. I asked him if the doctor ever told him to lose weight; he answered "no". In my opinion that is malpractice.
BTW Google "curcumin prostate cancer Alzheimer" and "cinnamon diabetes" if you want to know some real cheap, effective substances. I take capsules of each daily, cost pennies.
Now, if you're talking about some fanthom arthritic pain that comes and goes and you're told you need an MRI, or a CT scan or are sent for a sonogram, that's vastly different when other palliative measures should be considered first; i.e., an aspirin regimen, for example or nutritionals that are anti-inflammatory aides such as calcium/magnesium.
Getting yearly bloodwork as a preamble for annual exams is very important. Isn't that a "preventative" measure? Heart disease is epidemic - don't you want to know, even if you don't give a hoot, what your cholesterol/tryglecerides read?
Besides, with the new electronic system into place, it will save millions on duplicate testing. If you want to save money on healthcare, sart with the greedy pharmaceutical companies who scalp the public.
PSA tests absolutely do not save money. All men eventually get prostate cancer. 40% of US men will fail a PSA test at age 65, but essentially none will ever get symptoms or die from it. But if they listen to doctors they will have expensive prostate surgery. PSA tests themselves cost, and they cause millions of needless surgeries. They are a total waste of money. I'm 60, male. If you become same look into the facts before you needlessly get your prostate removed.
I was in medical imaging. MRIs, mammograms etc are officially called modalities or "scans", but radiologists jokingly refer to them as "scams" because they are oversold and don't work very well.
But I totally agree with you on prescription drugs. They and scans are responsible for our rising health care costs.