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German alternative cancer clinics: Combining experimental therapeutics with rank quackery and charging big bucks for it

Pauline Gahan in front of the Hallwang Private Oncology Clinic
A couple of months ago, I discussed patient deaths at an alternative medicine clinic in Europe, where a naturopath named Klaus Ross had been administering an experimental cancer drug (3-bromopyruvate, or 3-BP) to patients outside the auspices of a clinical trial. 3-BP is a drug that targets the Warburg effect, a characteristic of cancer cells first reported in the 1920s by Otto Warburg in which the cancer cell changes its metabolism to shut off oxidative phosphorylation (the part of glucose metabolism requiring oxygen that produces the most energy) to rely almost exclusively on glycolysis and anaerobic metabolism. From a cancer cell evolution standpoint, one can understand why cancer cells would behave this way, as this change allows them to survive in environments with much less oxygen than normal cells, but the side effect of the Warburg effect is that cancer cells consume a lot of glucose for their energy needs. Indeed, positron emission tomography (PET scanning) takes advantage of this characteristic of cancer cells to use glucose labeled with a positron-emitting isotope that accumulates in cells. The result is that cancer cells, which in general use a lot more glucose than normal cells, light up compared to the surrounding tissue, allowing the identification of areas suspicious for cancer. Targeting the Warburg effect is therefore a strategy to attack cancer cells preferentially.

Since I wrote about the tragic deaths of those cancer patients, I’ve been seeing stories about German alternative medicine cancer clinics popping up in my newsfeed over and over again. Intuitively, you’d think that a scientifically advanced economic powerhouse like Germany would have stricter regulations over the practice of medicine, but, the more I looked into these clinics, the more I realized that there are a lot of quack clinics in Germany every bit as quacky as any clinic in Tijuana, but with a twist. Like Mexican alternative medicine clinics, German clinics often charge enormous sums of money for treatments that range from the unproven to the dubious to pure quackery. However, in addition to the rank quackery, German cancer clinics include legitimate experimental drugs that are as yet unproven and might even only have cell culture or animal evidence supporting its potential efficacy. Indeed, 3-BP is just such an example. It is a legitimate candidate cancer drug that’s in the pipeline, having shown promise in cell culture and animal experiments, but that has no human data from systematic clinical trials yet, just a handful of anecdotes when it was tried in humans under desperate circumstances. Not surprisingly, Klaus Ross’ main clinic is in Germany, and, like so many other clinics there, he was administering an as-yet-unapproved drug to humans.

So, prodded by a couple of recent stories from the UK, I decided to take another look at these German cancer clinics.
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Posted in: Cancer, Clinical Trials, Health Fraud

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Diet and exercise versus cancer: A science-based view

Exercise time

One of the most effective spin techniques used by advocates of “integrative medicine” (also sometimes called “complementary and alternative medicine,” or CAM for short) to legitimize quackery has been to claim basically all non-pharmacologic, non-surgical interventions as “integrative,” “complementary,” or “alternative.” Thus, science-based interventions such as diet changes to treat and/or prevent disease, exercise, and other lifestyle alterations are portrayed as somehow so special that they need their own specialty, “integrative medicine,” even though they are simply part of medicine. I pointed this out a mere two weeks ago when I discussed the National Center for Complementary and Integrative Health (NCCIH) review of non-pharmacological treatments for pain. It was a systematic review that was essentially negative but spun as positive for some interventions and lacked some key analyses that a good systematic review includes, such as assessment of the quality of the studies included and evaluating them for bias.

Such were my thoughts over the weekend as I got into a Twitter exchange with an advocate of integrative medicine who was touting the benefits of diet as a cancer preventative and how a course in nutrition “opened her eyes.” That in and of itself wasn’t particularly annoying, although I strongly suspect that the nutrition course she took was not given by actual registered dietitians or other experts in science-based nutrition (she wouldn’t say when questioned). What was annoying is that she trotted out some tropes beloved by integrative medicine proponents, such as the claim that most doctors don’t do prevention because they get paid to treat. She was called out for it:

Oddly enough, on the same day a post from the American Society of Clinical Oncology (ASCO) came up in e-mail lists that discussed the actual evidence for the utility of diet and exercise for cancer prevention. It’s almost as though Twitter were telling me it was time for me to discuss this issue from a science-based perspective. So I will attempt to do so.
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Posted in: Cancer, Epidemiology, Nutrition

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“Liquid biopsies” for cancer screening: Life-saving tests, or overdiagnosis and overtreatment taken to a new level?

Could a blood draw be all you need to diagnose cancer and identify the best treatment for it? Not so fast...

Could a blood draw be all you need to diagnose cancer and identify the best treatment for it? Not so fast…

I’ve written many times about how the relationship between the early detection of cancer and decreased mortality from cancer is not nearly as straightforward as the average person—even the average doctor—thinks, the first time being in the very first year of this blog’s existence. Since then, the complexities and overpromising of various screening modalities designed to detect disease at an early, asymptomatic phase have become a relatively frequent topic on this blog. Before that, on my not-so-super-secret other blog, I noted that screening MRI for breast cancer and whole body CT scans intended to detect other cancers early were not scientifically supported and thus were far more likely to cause harm than good. That was well over ten years ago. Now we have a company offering what it refers to as a “liquid biopsy” for the early detection of cancer. I fear that this is the recipe for the ultimate in overdiagnosis. I will explain.

The problem, of course, is that disease progression, including cancer progression, is not always a linear process, in which the disease progresses relentlessly through its preclinical, asymptomatic phase to symptoms to complications to (depending on the disease) death. There is such a thing as disease that remains asymptomatic and never progresses (at which point it’s hard to justify actually calling it a disease). As I pointed out in my first SBM post on the topic, at least three-quarters of men over 80 have evidence of prostate cancer in autopsy series. Yet nowhere near three-quarters of men in their 80s die of prostate cancer—or ever manifest symptoms from it. This is what is meant by overdiagnosis, the diagnosis of disease that doesn’t need to be treated, that would never cause a patient problems.

When teaching medical students and residents, I frequently emphasize that overdiagnosis is different from a false positive because overdiagnosis does diagnose an actual abnormality or disease. For example, ductal carcinoma in situ (DCIS) diagnosed by mammography leading to a biopsy is a real pathological abnormality; it is not a false positive. We just do not know which cases of DCIS will progress to cancer and which will not, leading to a question of how DCIS should be treated or at the very least whether we should treat it as aggressively as we do now, particularly given that the apparent incidence of DCIS has increased 16-fold since the 1970s, all of it due to mammographic screening programs and the increased diagnosis of DCIS and early stage breast cancer has not resulted in nearly as much of a decrease in the diagnosis of advanced stage breast cancer as one would expect if early diagnosis were having an impact in reducing the diagnosis of late stage disease.

Overdiagnosis would not be such an issue if it didn’t inevitably lead to overtreatment. DCIS, for instance, is treated with surgery, radiation, and anti-estrogen drugs. Early stage prostate cancer used to be treated with radical prostatectomy, but now more frequently with radiation. Many of these men and women didn’t actually need treatment. We just don’t know which ones. This is why over the last six or seven years a significant rethinking of screening for breast and prostate cancer has occurred. There has been a backlash, of course, but the rethinking seems to have taken hold.

Not everywhere, of course. (more…)

Posted in: Basic Science, Cancer, Diagnostic tests & procedures, Public Health

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Recent Developments and Recurring Dilemmas in Cancer Screening: Colon, Lung, Thyroid

Cancer screening - lead time bias small

Screen detection and tumor growth rates. Cancers have different growth rates, which determine their potential to be detected by screening. Tumor A remains microscopic and undetectable by current technology (although more sensitive tests in the future might render it detectable). Tumor B eventually becomes detectable by screening (*), but its growth rate is so slow that it will not cause symptoms during the life of the individual; its detection will result in overdiagnosis. Tumor C is capable of metastasizing, but it grows slowly enough that it can be detected by screening (*); for some, this early detection will result in survival. Tumor D grows very quickly and therefore is usually not detected by screening. This will present as an interval cancer (i.e. detected clinically in the interval between screening examinations) and has a particularly poor prognosis. Note that of the four tumor types, only Tumor C has the potential to benefit from screening. Red dashed lines represent the natural history of a tumor in the absence of detection by screening. (Figure 1 from Gates, 2014).

A new stool DNA test was recently approved by the FDA for colon cancer screening. My first reaction was “Yay! I hope it’s good enough to replace all those unpleasant, expensive screening colonoscopies.” But of course, things are never that simple. I wanted to explain the new test for our readers; but before I could start writing, some other issues in cancer screening barged in and demanded to be included. They exemplify the dilemmas we face with every screening test. We have covered these issues before, but mainly in reference to mammography and prostate (PSA) screening. My article morphed into a CLT sandwich: colon, lung, and thyroid cancer screening.

The current issue of American Family Physician has a great article on cancer screening. It uses lucid graphics to illustrate lead time bias, length time bias, and overdiagnosis bias, as well the effect of varying tumor growth rates on screening success rates, all concepts that have been covered by Dr. Gorski here. Briefly, screening may do more harm than good if:

  1. It detects cancerous cells that never would have developed into invasive cancers or harmed the patient in any way;
  2. Early diagnosis and treatment decrease quality of life without reducing death rates; or
  3. The test falsely indicates cancer in patients who don’t have it or fails to indicate cancer in some who do. (more…)

Posted in: Cancer, Diagnostic tests & procedures

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Hyping Health Risks

Three kids on the same block were diagnosed with leukemia last year. That couldn’t happen just by chance, could it? There MUST be something in the environment that caused it (power lines, the chemical plant down the street, asbestos in their school, iPods, Twinkies?). Quick, let’s measure everything we can think of and compare exposures to other blocks and find an explanation.

That may be the common reaction, and it may seem plausible to the general public, but it’s not good science.

I have just read a book that does a great job of elucidating the pitfalls of epidemiologic studies, the problematic interface between science and emotion-laden public concerns, and the way environmental hazards have been hyped far beyond the evidence. Hyping Health Risks: Environmental Hazards in Daily Life and the Science of Epidemiology by Geoffrey C. Kabat.

He covers the uses, strengths and limitations of epidemiology, discusses the pros and cons of different study designs, and explains how to judge whether an association is causal.
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Posted in: Book & movie reviews, Science and the Media

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