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Early detection of cancer, part 2: Breast cancer and MRI

Note: If you haven’t already, you should read PART 1 of this two-part series. It defines several terms that I will be using in this post, and I don’t plan on explaining them again, given that they were explained in detail in Part 1. Of course, if you’re a medical professional and already know what lead time bias, length bias, and stage migration are, then it goes without saying that you should still read Part 1 for its scintillating prose.

ResearchBlogging.orgWhen last I left this topic three weeks ago, I had discussed why detecting cancer at ever-earlier stages and ever-smaller sizes is not necessarily an unalloyed good. At that time, I discussed in detail a landmark commentary in the New England Journal of Medicine entitled, Advances in Diagnostic Imaging and Overestimations of Disease Prevalence and the Benefits of Therapy. The article, although nearly 15 years old, rings just as true today in its cautioning doctors about whether ever-increasing diagnostic sensitivity that imaging technology and new blood tests were (and are) providing was actually helping patients as much as we thought it was. Before we dive into this problem as applied to breast cancer, let’s review what Drs. Black and Welch had to say about screening tests for breast cancer 15 years ago, as way of background and linking my last post and this one:

Before the widespread use of mammography, most breast cancers were discovered on physical examination, as palpable lumps. In one of the few studies to assess directly the accuracy of physical examination in screening for breast cancer, only 27 percent of tumors more than 1.0 cm in diameter and 10 percent of those less than 1.0 cm in diameter were detected by physical examination. However, the mean size of breast cancers detected by state-of-the-art screening mammography is about 1.0 cm, and many of the cancers detected as microcalcifications are only a few millimeters in size.

Again, prevalence depends on the degree of scrutiny. According to the Connecticut Tumor Registry, clinically apparent breast cancer afflicts about 1 percent of all women between the ages of 40 and 50 years. In a recent medicolegal autopsy study, however, small foci of breast cancer were found in 39 percent of women in this age group. Most cancers were in the form of ductal carcinoma in situ. Furthermore, over 45 percent of the women with cancer had two or more lesions, and over 40 percent had bilateral lesions. Although it has been argued that such small in situ lesions are not detected by and are therefore irrelevant to screening mammography, about half the lesions in that study were detected, usually as microcalcifications, on postmortem plain-film radiography of the resected breasts. Because of continual technical improvements and increasingly broad criteria for the interpretation of mammograms, the detection threshold for breast cancer has fallen considerably since the time of the Breast Cancer Screening Project of the Health Insurance Plan of Greater New York (1963 to 1975). This can explain the increased prevalence of cancer on mammographic screening, from 2.717 to 7.614 per 1000 examinations (with the incidence increasing from 1.517 to 3.214 per 1000 examinations). The lower detection threshold can also explain the increase in the percentage of carcinomas in situ (stage 0) among all mammographically detected cancers — from 12.7 percent to over 30 percent. The principal indication for biopsy has changed from suspicious mass to suspicious microcalcifications. This can explain why the reported incidence of breast cancer has increased and why most of the increase is in smaller lesions, particularly ductal carcinoma in situ.

About a year ago, three major articles hit the medical press that made me start thinking about this more than I had in the past. It’s my job, after all, because breast cancer surgery is a large part of my practice, and I do breast cancer lab-based research. What also tweaked me not to put off doing part 2 of this series is that, just two days ago, there was an abstract presented at the American Society of Clinical Oncology Meeting (where I still am today) that also serves to highlight just how difficult this question of integrating a test as sensitive as MRI into a screening regimen for and preoperative evaluation of breast cancer is and how MRI should fit into in this regimen can be.
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Posted in: Clinical Trials, Public Health, Science and Medicine, Science and the Media, Surgical Procedures

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The TACT is at least as Bad as We Predicted

I had wanted to follow Dr. Sampson’s discussion of “Healing Touch” with one of my own, because I had an interesting experience with one of its proponents years ago, and I’ll do that soon. I had also wanted to begin a series of posts about acupuncture, which I’ll also do eventually. Just yesterday, however, Liz Woeckner, co-author of our recently published critique of the NIH Trial to Assess Chelation Therapy (TACT), made a startling discovery: the TACT “Portal” website, intended for investigators and others associated with the trial and previously password protected, is now available to anyone: http://www.chelationwatch.org/s/tact/index.html It is a goldmine of information and I’ve barely begun to look at it, but so far it verifies much of what we’ve written and more. For example, the latest version of the Consent Form is dated 2006 and includes this statement under “risks”:

EDTA, or ethylenediamine tetraacetate is in the chelation solution. It is approved for use by the FDA as a treatment for lead poisoning but not for coronary artery disease.

Yet three Investigator Brochures, dating back to 2003, contain this language:

Edetate disodium USP should not be confused with its calcium salt (calcium edetate), which is used to treat lead toxicity.

We had called attention, in our article, to TACT literature repeatedly conflating Na2EDTA and the safer CaNaEDTA. Now we have reason to believe that this has been done cynically, with eyes wide open.

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Posted in: Clinical Trials, Medical Ethics, Politics and Regulation, Science and Medicine

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Changing the Rules of Evidence

My daughter, Julia, loves to play games and has a bit of a competitive streak. She can make any activity into a game and is adept at making up rules on the spot. When she was younger, like most children, she had a tendency to add to or change the rules on the fly – usually to ensure a favorable outcome for herself. “Oh, Daddy, I forgot to mention that the ball can bounce once and that still counts.”

It was an opportunity for me to gently teach her that in order for rules to work everyone has to know what they are ahead of time and you can’t change them after the fact. Her smile told me that even at five she intuitively knew this already – that changing or making up new rules was not fair. What I was really teaching her was that she wasn’t going to get away with it with me, and by extension that it is socially unacceptable to mess with the rules to suit oneself.

Adults are really no different than children in our basic emotional makeup. We all want to change the rules to suit our own needs. The true difference is that as we mature we become more socially sophisticated; we become more subtle in our manipulations, and we develop the capacity to rationalize our wants and desires. We also learn that we are playing a bigger game – the social game. So we adhere to the rules of fairness, even if it means losing a competition, because we want to succeed at the more important game of socialization. (I’m not making any moral or ethical judgments here, just observing human behavior.)

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Posted in: Clinical Trials, Science and Medicine

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“Chelation Therapy”: Another Unethical “CAM” Trial Sponsored by Taxpayers

Please forgive the promotion of our own work and the facile evasion of a full-length blog, but two of your faithful bloggers are co-authors of an article published this week:

Why the NIH Trial to Assess Chelation Therapy (TACT) Should Be Abandoned

Kimball C. Atwood IV, MD; Elizabeth Woeckner, AB, MA; Robert S. Baratz, MD, DDS, PhD; Wallace I. Sampson, MD

Medscape J Med.  2008;10(5):115.  ©2008 Medscape

Posted 05/13/2008

Available here.

You may be asked to “register”; don’t worry, it’s free. The article is very long, but the Introduction, Executive SummaryDiscussion, and Conclusion are reasonably succinct and make the important points. Readers who want to learn more details, who want to see more evidence for our assertions, or who are compelled by an odd fascination with crackpotism (my own weakness) will want to read more. Here is a small sample:

Abstract

The National Institutes of Health (NIH) Trial to Assess Chelation Therapy (TACT) was begun in 2003 and is expected to be completed in 2009. It is a trial of office-based, intravenous disodium ethylene-diamine-tetra-acetic acid (Na2EDTA) as a treatment for coronary artery disease (CAD). A few case series in the 1950s and early 1960s had found Na2EDTA to be ineffective for CAD or peripheral vascular disease (PVD). Nevertheless, a few hundred physicians, almost all of whom advocate other dubious treatments, continued to peddle chelation as an office treatment. They claim that chelation dramatically improves symptoms and prolongs life in 80% to 90% of patients. In response, academics performed 4 controlled trials during the 1990s. None favored chelation, but chelationists repudiated those findings.

We have investigated the method and the trial. We present our findings in 4 parts: history, origin and nature of the TACT, state of the evidence, and risks. We present evidence that chelationists and their organization, the American College for Advancement in Medicine, used political connections to pressure the NIH to fund the TACT. The TACT protocols justified the trial by misrepresenting case series and by ignoring evidence of risks. The trial employs nearly 100 unfit co-investigators. It conflates disodium EDTA and another, somewhat safer drug. It lacks precautions necessary to minimize risks. The consent form reflects those shortcomings and fails to disclose apparent proprietary interests. The trial’s outcome will be unreliable and almost certainly equivocal, thus defeating its stated purpose.

We conclude that the TACT is unethical, dangerous, pointless, and wasteful. It should be abandoned.

Readers of my postings on SBM will find more discussion (and abundant evidence) of familiar material: ethical breaches resulting from political incursions into science; the pitfalls, both scientific and ethical, of ignoring prior probability; a Dirty Secret of the Extraordinary Popular Delusion that is “CAM,” that much of what masquerades as sober research or the practice of “integrative medicine” was spawned by Laetrile; and widespread dishonesty in “academic CAM.”

Medscape Journal of Medicine invites readers to post comments or to send private letters to the editor for potential publication (and replies by yours truly, in this case). If you are so moved, you might consider posting comments in duplicate, both there and here on SBM, for the benefit of our select readership.

Posted in: Clinical Trials, Health Fraud, Medical Ethics, Politics and Regulation

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Near Death Experiences and the Medical Literature

MIRACLE MAX: See, there’s a big difference between mostly dead, and all dead. Now, mostly dead: he’s slightly alive. All dead, well, with all dead, there’s usually only one thing that you can do.

INIGO: What’s that?

MIRACLE MAX: Go through his clothes and look for loose change.

The Princess Bride

Can you trust anyone when they purport to tell you what the medical literature says? No. As an example we will use the issue of near death experiences, or NDE’s.

We will avoid the obvious paradox in this entry, sort of the ‘everything I say is a lie paradox’ that will cause computers in the Federation to shut down.

Why am I going to comment on this issue? Well, this months Skeptic has a back and forth between Michael Shermer and Deepak Chopra about life after death.

No. I am not going to comment on whether there is life after death. I am more interested in life during life, thank you very much. I’ll let the afterlife take care of itself.

But in their point counterpoint, they both refer to a Lancet article about NDE’s and it then begs the question:

Does anyone actually read or understand the literature they quote ?

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Posted in: Clinical Trials, Neuroscience/Mental Health, Science and the Media

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The Ethics of “CAM” Trials: Gonzo (Part VI)

Part V of this Blog argued that the NCCAM-sponsored trial of the “Gonzalez regimen” for cancer of the pancreas is unethical by numerous criteria.† To provide an illustration, it quoted a case history of one of the trial’s subjects, who had died in 2002.¹ It had been written by the subject’s friend, mathematician Susan Gurney. A similar story was told on ABC 20/20 in 2000, albeit not about a trial subject. Each of these cases demonstrates the wide breadth of Gonzalez’s quackery, as did his brush with the New York medical board during the 1990s.

This entry addresses some aspects of how those in charge of the trial failed in their duty to protect human subjects. By implication, it suggests what is necessary to prevent similar travesties in the future. It also addresses, to the small extent that the information exists, what appear to be the final ethical violations: first, that the trial will never be completed, thus having “expose[d] subjects to risks or inconvenience to no purpose.” Second, that Columbia University and the responsible investigators have no intention of explaining why.

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Posted in: Cancer, Clinical Trials, Medical Academia, Medical Ethics, Science and Medicine

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The Ethics of “CAM” Trials: Gonzo (Part V)

Part IV of this blog ended by observing that the NIH-funded trial of the “Gonzalez regimen” for cancer of the pancreas,† to have begun in March, 1999, was in trouble almost as soon as it started. As originally designed, it was to have been a randomized, controlled trial comparing gemcitabine, the standard chemotherapy, to the “Gonzalez regimen” of pancreatic enzymes, “supplements,” twice-daily coffee enemas, and other purported methods of “detoxification.” By June, 1999, according to Dr. John Chabot, the Columbia University surgeon acting as Principal Investigator (PI) of the trial, only 3 of the first 50 potential subjects had agreed to be randomized, and none of the three met the eligibility criteria. By January, 2000 it had become clear that the trial would not accrue a sufficient number of subjects if it remained randomized, because almost all of the potential subjects were intent on being in the “nutritional,” ie, the Gonzalez arm.

Trouble with Randomizing

The investigators at Columbia therefore decided to change the protocol to a “single-armed, non-randomized case-cohort study where patients will only be enrolled in what was the nutritional arm.” Paradoxically, PI John Chabot had recently explained, at the 1999 Comprehensive Cancer Care Conference of James Gordon’s Center for Mind-Body Medicine, why this would not be a scientifically sound design:

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Posted in: Clinical Trials, Health Fraud, Medical Academia, Medical Ethics

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Conflict of Interest in Medical Research

The cornerstone of science-based medicine is, of course, scientific research. The integrity and quality of biomedical research is therefore of critical importance and to be thoughtfully and jealously guarded, if we care about maintaining an optimal standard of care. There are many threats and hazards to the institutions of medical research – mostly ideological. One that has not been discussed much on this blog but has been in the news recently is that of conflict of interest. Upon close examination this is a more complex issue than it may at first appear.

The most recent controversy over conflicts of interest were sparked by an article published in JAMA in which the authors allege that published studies that downplayed the risks of Vioxx (A Cox-2 inhibitor marketed as a pain killer that was removed from the market for increased cardiac risk) were in fact ghost-written by employees of Merck, the manufacturer of Vioxx. The names of two academic researchers were then attached to the studies to give them legitimacy. If true this is a damning episode, and no one would reasonably disagree with the contention that companies writing research on their own products represents an unacceptable conflict of interest. For the record, both Merk and the one surviving academic deny the accusations completely.

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Posted in: Clinical Trials, Medical Ethics

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The Ethics of “CAM” Trials: Gonzo (Part IV)

A Review; then Back to the Gonzalez Regimen†

Part I of this blog introduced the topic of the “Gonzalez regimen” for treating cancer: “Intensive Pancreatic Proteolytic Enzyme Therapy With Ancillary Nutritional Support” and “detoxification” with twice daily coffee enemas, daily “skin brushing,” “a complete liver flush and a clean sweep and purge on a rotating basis each month,” and more. The topic was occasioned by the federal Office for Human Research Protections having recently cited Columbia University, for the second time, for violations of human subject protections in its NIH-funded trial of Gonzalez’s method as a treatment for cancer of the pancreas.

Part I discussed the implausible and bizarre regimen and cited Gonzalez’s troubles with malpractice suits and with the New York medical board during the 1990s. It ended by wondering what could have induced the NIH to give a $1.5 million grant to Columbia University to study the method.

Parts II and III began to answer that question, tracing some of the key events and individuals from the Laetrile wars in the 1970s to the NCI-funded trial of Laetrile reported in 1982, to the ”immuno-augmentative therapy” (IAT) battles of the mid-’80s, to the Report on “Unconventional Cancer Treatments” by the Congressional Office of Technology Assessment (OTA) in 1990, which in turn led to the NCI adopting its “Best Case Series Program” in 1991.

The end of Part III hinted that the conspiracy mongering that had greeted every attempt by the government to explain its positions on implausible cancer treatments, from Laetrile to the OTA report, ultimately led to the creation of the Office of Alternative Medicine (OAM) at the NIH, also in 1991. There is plenty of evidence for that, both from the conspiracy mongers themselves and from more level-headed observers. Each time the government acted—to fund a trial of Laetrile, to solicit the OTA report and propose a study of IAT, to establish the NCI “Best Case Series” program, and to establish the OAM—it was not because of scientific or medical considerations, but because of political pressure. More on that from time to time, but now back to Dr. Gonzalez.

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Posted in: Cancer, Clinical Trials, Health Fraud, Medical Academia, Medical Ethics

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Borderlines in research

This is a slight departure from the usual fare of pseudoscience, but a matter that should concern us because of the vulnerability this matter confers on medicine – the borderline practices of major medical centers. The article can be viewed here.

Several days ago the San Francisco Chronicle printed a second article about the plight of a 37 year old woman (EP) with an inflammatory breast cancer who was denied insurance coverage for an expensive treatment, high-dose chemotherapy with autologous bone marrow (or stem cell) transplant or infusion (HDCT/BMT or SDI.) The institution is the MD Anderson Cancer Center in Houston. The problem is that although the treatment is effective, it is no moreso than moderate dose HDCT without the marrow or stem cell infusion, and also is more expensive and has significant morbidity.

Inflammatory breast cancer is a highly aggressive form that is usually regarded as “advanced” when diagnosed, that is, spread beyond the breast and regional lymph nodes. One cannot tell from the article whether EP’s cancer spread is documented or implied. But because of the poor prognosis and presumed incurability in either case, options are limited. In the 1980s -90s, HDCT/BMT was thought to be a promising method on the basis of studies that showed a prolonged disease-free and overall survival compared to results of prior studies using more conservative treatment. The problem then was that the studies were uncontrolled.

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Posted in: Cancer, Clinical Trials, General, Medical Ethics

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