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The uncertainty surrounding mammography continues

Screening mammography

Mammography is a topic that, as a breast surgeon, I can’t get away from. It’s a tool that those of us who treat breast cancer patients have used for over 30 years to detect breast cancer earlier in asymptomatic women and thus decrease their risk of dying of breast cancer through early intervention. We have always known, however, that mammography is an imperfect tool. Oddly enough, its imperfections come from two different directions. On the one hand, in women with dense breasts its sensitivity can be maddeningly low, leading it to miss breast cancers camouflaged by the surrounding dense breast tissue. On the other hand, it can be “too good” in that it can diagnose cancers at a very early stage.

Early detection isn’t always better

While intuitively such early detection would seem to be an unalloyed Good Thing, it isn’t always. Although screening for early cancers appears to improve survival, the phenomenon of lead time bias can mean that detecting a disease early only appears to improve survival even if earlier treatment has no impact whatsoever on the progression of the disease. Teasing out a true improvement in treatment outcomes from lead time bias is not trivial. Part of the reason why early detection might not always lead to improvements in outcome is because of a phenomenon called overdiagnosis. Basically, overdiagnosis is the diagnosis of disease (in this case breast cancer but it is also an issue for other cancers) that would, if left untreated, never endanger the health or life of a patient, either because it never progresses or because it progresses so slowly that the patient will die of something else (old age, even) before the disease ever becomes symptomatic. Estimates of overdiagnosis due to mammography have been reported to be as high as one in five or even one in three. (Remember, the patients in these studies are not patients with a lump or other symptoms, but women whose cancer was detected only through mammography!) Part of the evidence for overdiagnosis includes a 16-fold increase in incidence since 1975 of a breast cancer precursor known as ductal carcinoma in situ, which is almost certainly not due to biology but to the introduction of mass screening programs in the 1980s.

As a result of studies published over the last few years, the efficacy of screening mammography in decreasing breast cancer mortality has been called into question. For instance, in 2012 a study in the New England Journal of Medicine (NEJM) by Archie Bleyer and H. Gilbert Welch found that, while there had been a doubling in the number of cases of early stage breast cancer in the 30 years since mass mammographic screening programs had been instituted, this increase wasn’t associated with a comparable decrease in diagnoses of late stage cancers, as one would expect if early detection was taking early stage cancers out of the “cancer pool” by preventing their progression. That’s not to say that Bleyer and Welch didn’t find that late stage cancer diagnoses decreased, only that they didn’t decrease nearly as much as the diagnosis of early stage cancers increased, and they estimated the rate of overdiagnosis to be 31%. These results are in marked contrast to the promotion of mammography sometimes used by advocacy groups. Last year, the 25 year followup for the Canadian National Breast Screening Study (CNBSS) was published. The CNBSS is a large, randomized clinical trial started in the 1980s to examine the effect of mammographic screening on mortality. The conclusion thus far? That screening with mammography is not associated with a decrease in mortality from breast cancer. Naturally, there was pushback by radiology groups, but their arguments were, in general, not convincing. In any case, mammographic screening resulted in decreases in breast cancer mortality in randomized studies, but those studies were done decades ago, and treatments have improved markedly since, leaving open the question of whether it was the mammographic screening or better adjuvant treatments that caused the decrease in mortality from breast cancer that we have observed over the last 20 years.

Given that it’s been a while since I’ve looked at the topic (other than a dissection of well-meaning but misguided mandatory breast density reporting laws a month ago), I thought now would be a good time to look at some newer evidence in light of the publication of a new study that’s producing familiar headlines, such as “Mammograms may not reduce breast cancer deaths“.

Here we go again.
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Posted in: Cancer, Public Health

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Mandatory breast density reporting legislation: The law outpaces science, and not in a good way

Over the years, our bloggers here at Science-Based Medicine have written time and time again about the intersection of law and science in medicine. Sometimes, we support a particular bill or law, such as laws to protect children against religion-inspired medical neglect; laws making it harder for manufacturers of homeopathic “medicines” to deceive the public; or California Bill AB 2109, a bill whose intent was to make it more difficult for parents to obtain nonmedical exemptions to vaccine mandates but whose implementation after being passed into law was profoundly sabotaged by Governor Jerry Brown. or, more recently, California SB 277, a bill currently wending its way through the California legislature that would eliminate nonmedical exemptions to school vaccine mandates and has, not surprisingly, engendered extreme resistance from the antivaccine crowd, including by Robert F. Kennedy, Jr. In the vast majority of cases we explain how the law lets us down when it comes to science in medicine, and, unfortunately, examples are many: Naturopathic licensing laws; supplement regulation (or, more appropriately, lack of regulation); misguided, deceptive, and patient-hostile “right-to-try” laws; state laws regulating medical practice that allow quackery to flourish unchecked; laws regulating pharmaceutical cost transparency that ask the wrong question.

The case I will discuss here is unusual in that it is a case of the law getting ahead of what the science says in a manner that will likely do little, if any, good for patients, cause a lot of confusion until the science is worked out better, and end up costing patients money for little or no benefit. I am referring to laws mandating the reporting of high-breast-density to women with dense breasts undergoing mammography. These laws are sweeping the country (albeit not as rapidly as “right-to-try” laws), with a total of 22 states having passed them as of today since Connecticut became the first to do so in 2009. The most recent of these laws went into effect in my own state of Michigan exactly one week ago:

Women with dense breast tissue — the sort that can hide potentially deadly tumors from routine mammograms — must be notified in writing and encouraged to consider additional tests under a new state law that is effective Monday.

While mammograms remain the gold standard for detecting breast tumors, they’re less reliable in almost half of women with dense breast tissue. Dense or fibrous tissue shows up as splotches of white on a mammogram — so do tumors.

That will likely surprise many of the millions of women who rely on mammography for catching the earliest signs of cancer, said Nancy Cappello. The Connecticut woman was shocked in 2004, when her gynecologist found a lump — advanced cancer that had already spread to her lymph nodes — just months after a mammogram deemed her cancer-free.

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Posted in: Cancer, Politics and Regulation, Public Health

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Let food be thy medicine and medicine be thy food? The obsessive worship of “medicinal foods”

Let food be thy medicine and medicine be thy food? The obsessive worship of “medicinal foods”

Let food be thy medicine and medicine be thy food.

– attributed to Hippocrates

Who said anything about medicine? Let’s eat!

– attributed to one of Hippocrates forgotten (and skeptical) students

 

Who hasn’t seen or heard Hippocrates’ famous quote about letting food be your medicine and your medicine your food? If you have Facebook friends who are the least bit into “natural” medicine or living, you’ve almost certainly come across it in your feed, and if you’re a skeptic who pays the least bit of attention to what’s going on in the quackosphere you will almost certainly have seen it plastered on a picture as a meme, either using a picture of Hippocrates or pictures of plates of green, leafy vegetables, or both. I like to view the fetishization of “food as medicine,” to cite Hippocrates, as one of the best examples out there of the logical fallacy known as the appeal to antiquity; in other words, the claim that if something is ancient and still around it must be correct (or at least there must be something to it worth considering).

Of course, just because an idea is old doesn’t mean it’s good, any more than just because Hippocrates said it means it must be true. Hippocrates was an important figure in the history of medicine because he was among the earliest to assert that diseases were caused by natural processes rather than the gods and because of his emphasis on the careful observation and documentation of patient history and physical findings, which led to the discovery of physical signs associated with diseases of specific organs. However, let’s not also forget that Hippocrates and his followers also believed in humoral theory, the idea that all disease results from an imbalance of the “four humors.” It’s also amusing to note that this quote by Hippocrates is thought to be a misquote, as it is nowhere to be found in the more than 60 texts known as The Hippocratic Corpus (Corpus Hippocraticum).

As Diana Cardenes argues:

But Hippocratic doctors clearly saw a difference between food and medicines. In fact, food was considered as a material that could be assimilated after digestion (e.g. the air was also food) and converted into the substance of the body. For example, food was converted into the different parts of the body such as muscles, nerves, etc. By contrast, the concept of medicines at the time was a product which was able to change the body’s own nature (in terms of humor quality or quantity) but not be converted into the body’s own substance. Thus a food wasn’t considered a medicine. A possible root of the food-medicine confusion is the following cryptic phrase found in the work On Aliment: “In food excellent medication, in food bad medication, bad and good relatively”.3 This text is nowadays attributed to the Hellenistic period, but was considered to be Hippocratic in Antiquity by Galenus in particular.

Now, it is certainly true that Hippocrates and his followers used diet to treat many illnesses, it’s not really clear what sort of success they had. However, this ancient idea that virtually all disease could be treated with diet, however much or little it was embraced by Hippocrates, has become an idée fixe in alternative medicine, so much so that it leads its proponents twist new science (like epigenetics) to try to fit it into a framework where diet rules all, often coupled with the idea that doctors don’t understand or care about nutrition and it’s big pharma that’s preventing the acceptance of dietary interventions. That thinking also permeates popular culture, fitting in very nicely with an equally ancient phenomenon, the moralization of food choices (discussed ably by Dr. Jones a month ago).
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Posted in: Cancer, Nutrition

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Florida strikes out against Brian Clement

CBC interview with Brian Clement.

CBC interview with Brian Clement.

Brian Clement is a charlatan. Unfortunately, that doesn’t seem to be a problem for the State of Florida. I made two (which turned into three) attempts to get the state to take action against Clement or the Hippocrates Health Institute, where he serves with his wife Anna Maria Gahns-Clement as co-director. All of them failed. Brian Clement slithered through the cracks in Florida law each time.

Before we get into the details of Florida’s failure to act, a bit of history (and there is plenty of it) is in order.

In recent months, Clement’s sordid cancer quackery has been well-documented in the media as well as in the science “blogosphere”. (I’ve listed what I hope is a — but almost certainly isn’t — complete blog archive at the end of this post. Many of the Canadian Broadcasting Corporation [CBC] and other news reports are linked in these posts.) Most of the coverage has centered on two Canadian girls suffering from lymphoblastic leukemia whose parents pulled them from conventional cancer therapies, which gave them an excellent chance of survival, in favor of treatment at the Hippocrates Health Institute (HHI), a sprawling spa in West Palm Beach, Florida, licensed as a massage establishment by the state.

Clement gave a talk in Canada, in 2014, claiming “we’ve had more people reverse cancer than any institute in the history of health care.” (“We” is the operative word here, because it later served as Clement’s ticket to avoid prosecution by the Florida Board of Medicine, as you shall soon find out.) The girls’ families were impressed.

Sadly, one of the girls, Makayla Sault, died earlier this year. The other, identified only as “JJ” in the media because of a publication ban, has returned to conventional treatment. However, her mother apparently remains under the influence of Clement: JJ is restricted to a raw foods diet and is still being followed, if that is the right word, by HHI. (more…)

Posted in: Cancer, Health Fraud, Legal, Nutrition, Politics and Regulation, Science and the Media

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Escharotic Treatment for Cervical Dysplasia: A New Incarnation of Black Salve?

Flowers of the bloodroot plant, Sanguinaria canadensis.  You're welcome, I could have used a very different image (warning: gross bordering on horrifying).

Flowers of the bloodroot plant, Sanguinaria canadensis. You’re welcome, I could have used a very different image (warning: gross bordering on horrifying; click on image to see it).

Cervical dysplasia is a precancerous condition picked up by Pap smears. It is most often caused by human papillomavirus (HPV) infection. Mild cases may resolve spontaneously and can be followed by observation with frequent Pap smears, but cervical dysplasia can progress to cancer. The standard treatment is to remove the abnormal cells with a cone biopsy (using a knife) or a Loop Electrosurgical Excision Procedure (LEEP) using a wire loop heated by electricity. Those procedures not only treat the disease, but they provide a pathology specimen that can be examined to rule out more serious or invasive disease. Both LEEP and cone biopsy are 85-90% effective in removing all the abnormal cells. If cancer is suspected, a cone biopsy is preferable because LEEP may damage the edges of the specimen and make it more difficult to interpret. Otherwise, LEEP is often preferred because it is less expensive and doesn’t require anesthesia or an operating room. I have discussed misguided attempts by alternative medicine practitioners to treat cervical dysplasia before.

Surgery is often perceived as scary and not “natural,” so it’s not surprising that a “natural” treatment has been devised to replace surgery. Escharotics are corrosive salves that get their name from the thick dry scab that they can produce called an eschar. The “natural” escharotic treatment alternative for cervical dysplasia involves applying a solution of bloodroot (Sanguinaria canadensis) and zinc chloride. They claim that the solution selectively kills abnormal cells of the cervix while leaving healthy cells unaffected. That claim is almost certainly false, and the efficacy and safety of escharotic treatment has not been properly tested or compared to conventional treatment. (more…)

Posted in: Cancer, Herbs & Supplements, Naturopathy, Obstetrics & gynecology

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Cancer Centers and Advertising Practices

Video advertisement for the Cancer Treatment Centers of America, hosted on their website. Note at the bottom the statement “No case is typical. You should not expect to experience these results” (click to embiggen).

You have probably seen the TV commercials or other ads for Cancer Treatment Centers of America. They make it sound like “the place to go” if you have cancer. They claim to be “different,” to combine the best cancer technologies with natural therapies in a humane, patient-centered approach that helps you fight the disease and maintain your quality of life. They offer a kinder, gentler, more effective oncology. Those ads are misleading.

Dr. Gorski has written about the practices of Cancer Treatment Centers of America here and here. He has shown how they “integrate” real medicine with nonsense like homeopathy and how they misrepresent components of science-based medicine like exercise and diet, re-branding them as “alternative.”

A recent study by Vater et al. published in the Annals of Internal Medicine asked “What are cancer centers advertising to the public?” They found that the ads appealed to emotion, failed to provide important information, falsely portrayed testimonials as typical, and should be viewed as critically as any other advertising. (more…)

Posted in: Cancer, Medical Ethics, Science and the Media

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Angelina Jolie, surgical strategies for cancer prevention, and genetics denialism (revisited)

Angelina Jolie

Angelina Jolie

Sometimes, weird things happen when I’m at meetings. For example, I just got home from the Society of Surgical Oncology (SSO) meeting in Houston over the weekend. Now, one thing I like about this meeting is that, unlike so many other meetings these days—cough, cough, ASCO, I’m looking at you—at the SSO there wasn’t a single talk I could find about “complementary and alternative medicine” (CAM) or, as its proponents like to call it now, “integrative medicine.” It’s also a great chance to get caught up on new science and clinical guidelines in cancer surgery, as well as to see people I tend only to see at these meetings.

However, I must admit that by the last day I tend to be “meeting-ed” out and sometimes my attention wanders. Unfortunately, there are ample ways to indulge that attention deficit. Actually, it’s my iPhone. And it’s Twitter. So it was an odd coincidence that right after a talk by Dr. Deanna Attai about whether surgical oncologists can or should offer genetic counseling services to their patients, when I somehow let myself get into an exchange with Sayer Ji, the “natural health expert” responsible for GreenMedInfo, over BRCA1 mutations and the risk of breast and ovarian cancer, in other words, exactly the sort of thing that Dr. Attai had just discussed. For example:

After a bit of back-and-forth, I got fed up:

This minor Twitter exchange came about because of Angelina Jolie’s announcement in a New York Times op-ed last week entitled “Diary of a Surgery” that she had had her ovaries removed to prevent ovarian cancer due to her being a carrier of a high-risk mutation in BRCA1. As you might recall, I wrote about Jolie’s case two years ago, when she first announced in a NYT op-ed entitled “My Medical Choice” that she had undergone a bilateral mastectomy with reconstruction to decrease her BRCA1-related risk of breast cancer. Although I had discussed the story before, I thought it worth doing again here in a bit more detail. (more…)

Posted in: Basic Science, Cancer, Surgical Procedures

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Ken Burns Presents Cancer

Note: I wrote two posts today to alert readers to two upcoming television events in time for them to plan their viewing. See the second post for an announcement about a film on scientology, along with an article about Scientology’s War on Medicine that I wrote for Skeptic magazine.

Ken Burns

Filmmaker Ken Burns

Ken Burns has made a lot of outstanding films. His The Civil War has been listed as second only to Nanook of the North as the most influential documentary of all time. I was delighted to learn that he had applied his exceptional skills to a topic that is very important to us on the Science-Based medicine blog, cancer. His film is based on the Pulitzer Prize-winning book by Siddhartha Mukherjee, The Emperor of all Maladies: A Biography of Cancer.

I reviewed Mukherjee’s book in 2010. He is an oncologist and cancer researcher and also a superb writer. I characterized his book as:

a unique combination of insightful history, cutting edge science reporting, and vivid stories about the individuals involved: the scientists, the activists, the doctors, and the patients. It is also the story of science itself: how the scientific method works and how it developed, how we learned to randomize, do controlled trials, get informed consent, use statistics appropriately, and how science can go wrong.

I continue to think it is the best book ever written on cancer.

The film interviews Mukherjee and many of the researchers and patients whose stories appear in the book. If you haven’t read the book, it will give you an idea what it’s about. If you have read the book, you will enjoy it even more as you meet the people you have read about. It covers the history of cancer as well as the most recent scientific developments and is very optimistic about the future.

The movie is scheduled to premiere March 30 – April 1 at 9 PM EST on PBS, in 3 parts with a total duration of 6 hours. You can watch the trailer online. The producers sent me a press preview 1-hour highlight reel and I was very impressed. I can’t wait to watch the whole thing. I hope you will be able to watch it too.

Posted in: Announcements, Book & movie reviews, Cancer

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Medical marijuana as the new herbalism, part 3: A “cannabis cures cancer” testimonial

Medical marijuana as the new herbalism, part 3: A “cannabis cures cancer” testimonial

It’s been a while since I discussed medical marijuana, even though it’s a topic I’ve been meaning to come back to since I first dubbed medical marijuana to be the equivalent of herbalism and discussed how the potential of cannabinoids to treat cancer has been, thus far, unimpressive, with relatively modest antitumor effects. The reason I refer to medical marijuana as the “new herbalism” is because the arguments made in favor of medical marijuana are very much like arguments for herbalism, including arguments that using the natural plant is superior to using specific purified cannabinoids, appeals to how “natural” marijuana is, and claims of incredible effectiveness against all manner of diseases, including deadly diseases like cancer, based on anecdotes and testimonials. Now, as I pointed out before, not only am I not opposed to the legalization and regulation of marijuana for recreational use, even though I’ve never tried it myself, but I support it. What I do not support are claims for medical effects that are not backed up with good scientific evidence, and for medical marijuana most claims fall into that category. That’s why I tend to view medical marijuana as a backdoor way to get marijuana legalized. Personally I’d rather advocates of marijuana legalization drop the charade, argue for legalization, and stop with the medical nonsense.

The last time around, I discussed the evidence supporting claims that “cannabis cures cancer” and found them to be wanting based on science. I didn’t however, discuss the “cannabis cures cancer” testimonial machine that drives the claim that marijuana is useful for treating cancer; at least, I only touched on it by discussing briefly Rick Simpson, who claims that his hash oil cures approximately 70% of patients with terminal cancer and a published anecdote in which it was claimed that hemp oil was effective in treating acute lymphoblastic leukemia. (It wasn’t. At least, the evidence presented was not convincing.) Since then, I’ve wanted to revisit the topic of “cannabis cures cancer” testimonials, and, for whatever reason, now seems like a good time to do it.
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Posted in: Cancer, Herbs & Supplements

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Florida tells Brian Clement to stop practicing medicine

This is a screenshot from the website of the Hippocrates Health Institute, showing its grounds.

Screenshot of the Hippocrates Health Institute’s website

 
Note: Also posted today is a brief profile of a new blog, Naturopathic Diaries: Confessions of a Former Naturopath, by Britt Marie Deegan Hermes, a trained naturopath who became disillusioned with her profession. I encourage you to have a look!

The State of Florida has finally taken action against Brian Clement.

David Gorski, Orac, and the Canadian media, especially the Canadian Broadcasting Corporation (CBC), have done an excellent job of chronicling the activities of “Dr.” Clement. All have reported on Florida’s taking action against Clement. I’ll give a brief background here, most of which comes from Dr. Gorski’s most recent post, as well as add some information and observations to theirs.

Hippocrates Health Institute, located in West Palm Beach, Florida, is licensed as a massage establishment by the state and run by Brian Clement and his wife, Anna Maria Gahns-Clement. Clement and Hippocrates came to the attention of the Canadian media when, last year, the families of two Canadian aboriginal girls withdrew their children from conventional cancer treatment, including chemotherapy. Prior to that, Clement had basked in the glory of fawning reports from local media, one of which described him as having an “inimitable, engaging style.” Another described him as coming “fresh from a detoxifying sauna” to the interview.

Had they completed conventional treatment, both girls had a very good chance of survival. The families opted instead for traditional medicine as well as “alternative medicine” at Hippocrates. Each paid a reported $18,000 for participation in a “Life Transformation Program” there. This included, for at least one of the girls, cold laser therapy, vitamin C injections and a strict raw vegetable diet.

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Posted in: Cancer, Health Fraud, Legal, Naturopathy, Nutrition, Politics and Regulation

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