The [false]positive side of screening

Screening for Disease: Is earlier always better?

That title sounds a little wrong, you are thinking 'well, yes of course it is'. But bare with me. We have all heard of screening tests and are likely to have been through them. What is the harm in this? There is a lot of misinformation that is congregated around screening tests, leading to a lot of misunderstanding. Superficially, it appears to be good advice to give to ‘get something or other checked’. If there is something wrong in your body, you’d want to get it checked, yes? So, logically, we should be tested for everything regularly, yes? Well, no. We have an unfortunate thing in science called false positive. Meaning we would get a lot of anomalous results leading to a diagnosis and further tests to analyse something that isn’t actually there. 

Screening healthy people is a task that should be approached with caution. If you decline a screening, you will always have a little nagging voice in your head saying “what if?’ – you will, it is the nature of the human mind. So, should you have been offered the screening in the first place? I am going to focus on one type of screening in this blog; PSA. This is due to me researching into it naturally, and was not all too shocked at the information found. It was something I always somewhat knew, but not quite to this extent.

Prostate Screening

Prostate cancer is a very common cancer in men, occurring worldwide. There are two categories within prostate cancer, we have the aggressive and high death rate form and the slow growing, less likely to even have any symptoms. The latter of the two is most prominent and never really progresses to cause any health dangers during a patients’ lifetime, it is thought that 50% of men actually have the cancerous cells present - which will not develop. The screening test for prostate cancer is blood test in which they are looking for prostate specific antigen (PSA). A PSA test is looking at the levels of antigen in the blood, the test isn’t a ‘yes it is there’ or ‘no it is not there’, it requires interpretation. In an ideal world, we would like to have the rapid growing, life threatening cancers detected rather than the slow growing cancers as these don’t normally threaten a patients’ life. The side effects of prostate surgery to remove the cancer are invasive, scarring and leads to impotence, incontinence and cardiac problems.

PSA

PSA is an enzyme that is produced by prostate cells. Small amounts of PSA are observed in the blood at around 0.1-2.5ng/ml. Although, this appears to be very convoluted in the literature, many report the level is around 4-10ng/ml. So, if we don’t really have a consensus of the level that should be present normally, why would we look at it to detect cancers? These levels are said to be “normally” raised when prostate cancer is present. However, there are many other things that will effect PSA levels, including: ejaculation, weight, aspirin, infections and non-cancerous tumours. Evermore and more shockingly there is no clear cut-off level in which medical professionals use to differentiate those who have cancer and those who do not based on PSA levels. It is reported that 1 in 5 with clinically significant cancer will have a PSA level that is within the ‘normal’ reported range. If a doctor is using the 2.5nm/ml as the cut off, he could report cancer in a case with a PSA level <4.0 but higher than 2.5ng/ml. Even this report published by harvard have a different view of the levels that vary with age. Despite these limitations and high ability for misinterpretation, PSA routine testing is advised by medical professionals and companies that are selling these tests.  

 

Is there any harm in this?

Two questions that are required with any screening technique:

• Is there evidence to prove that early detection equates to a better overall outcome?
• Is there any harm from the testing?

In 2010, a systematic review was published in Biomedical Journal concluded that, as expected, PSA screening increased the likelihood prostate cancer diagnosis. However, it was found that there was no evidence of any impact on the death rate from the cancer itself (or the death rate overall for that matter). Risk factors, age and disease all need to be taken into consideration. Double blind randomized trials give very conflicting results with regards to the effectiveness and the test concentrates on disease specific mortality as opposed to the mortality overall. Richard Ablin, the discoverer of PSA recently wrote that the PSA test is being misused and is highly unreliable. Talking to New Scientist, Dr Ablin was reported stating:

“So, first is that PSA is not cancer-specific. Second, the level of PSA deemed worrying is arbitrary – 4 nanograms per millilitre or higher. As PSA is not cancer-specific, no level is diagnostic. Third, prostate cancer can be aggressive or, more often, very slow-growing. We can’t tell which is which.

Last, many men will develop prostate cancer by age 70. If an older man has a PSA level that prompts a biopsy, it is likely you will find cancer. Since you can’t tell if it’s aggressive, many men get treated unnecessarily – and risk life-altering side effects including impotence and incontinence”

 Source

This is all backed up by surmountable clinical trials. A study published in The New England Medical Journal screened over 1000 subjects before they saved one life. This lead, on average, to around 50 false positive patients, many of which unnecessarily undertook radiation therapy or even surgery. To put that into a simpler visual, this was taken from the Australian public health: 

“you have to screen 1408 men and treat an additional 48 men to prevent one prostate cancer death over 9 years. In other words, only 1 of those 48 men is going to benefit over the next 9 years; the other 47 … have undergone treatment for no benefit within this period.”

As stated prior, the treatment isn’t exactly nice and the side effects do change your life. We aren't seeing any better overall outcomes if we are including the unnecessary diagnoses (which we are) and we have a lot of harm from the testing, the over diagnosis. Thus, the two points that give the screening processes validation do not actually work.

Conclusion

Prostate cancer screening is easy, its just a blood test. But the results and the fallout are unaccountable. If 50% of men have the cancerous cells that wont progress into anything, then is it rational to have them undertake surgery? This screening method, like many others, is shadowed with over-diagnosis and the side effects from the treatment measures are significantly debilitating and life changing. So, should this still be being used? The decision is yours, the evidence is conflicting and mostly non-existent in the case for this particular screening technique. Don’t be fooled, this isn’t the only screening that actually has little success rate, there are many others - just as there are many others that are very effective. I am not discouraging (or trying to discourage) people from being screened from cancers, I just think there are many cases where it causes more harm and panic than good. At the bare minimum, the limitations of this and other screening processes should be clarified and communicated to a patient before the screening is carried out. 

There are plenty of books with sections on screening and the consensus amongst scientists with mass reviews of the evidence. I implore you to read them. 

Biomagnetics: Why are we still attracted?

Magnetic Healing

 I have been fortunate to have only red about this, but never really seen it, until know. Moving to a smaller city I have noticed a lot more chiropractic/homeopathic practices than I really do care to see. Whilst out shopping today I saw a fairly big stall branded ‘Magnetic Healing’ with a tagline of ‘Walk away pain free today; diabetic foot care’. I was more astonished by the amount of people crowding the stall than the stall itself. I first read about this in around 2013 and was thankful I had never seen it in the U.K., having only seen aspects of it before, seeing a full blown shop dedicated to it made me a little uneasy. 

What is Magnetic Healing?

Essentially, magnetic healing is exactly what it says; using magnets to heal pain. These magnets are in the form of charms, insoles and braces sold with the claims that they can relieve pain, increase energy and have a positive impact on mental and physical agility. It seems that the general public in the U.K. are still under the notion that pain can be healed by the use of magnetic energy. 

Source

Practitioners claim that the magnetic fields can positively effect blood and underlying tissues. I think this has gained much credibility via the use of magnets in clinical medicine. We use Magnetic Resonance Imaging (MRI) and we evaluate brain function with the measure of electrical impulses that travel through it. These practices are based on sound science and through years of research. As there is potential for a market by exploiting and bastardising magnetic properties, there are quacks to fill it. Essentially, what these people are selling are just regular magnets, such as the ones you put on your fridge. As you probably (hopefully) know, these have absolutely no effects. They will not penetrate beyond a few mm, let alone your skin to your tissues. Factually, haemoglobin isdiamagnetic (weakly, when oxygenated) the magnets, as stated, have fields way to low to have any effect (this website has some helpful diagrams and a much more in-depth explanation of this). If our body was affected by this weak of a magnet, then surely: 

 

a)    MRI would be made redundant

b)    We would be effected all the time

Any Evidence?

No. Only evidence (of value) is to the contrary. A study published quite a good while ago (1991) in The Journal of Nuclear Medicine studied the effects of magnets on the body and found that strengths of up to 1 Tesla had absolutely no effect. Many practitioners take away any basis of science and claim the effects are on the electromagnetic energy around the body, balancing and energising our auras. It has also been propagated as a treatment for cancer, diabetes and autism...

In 2008, a systematic review of all credible magnetic therapy studies published in The Focus on Alternative and Complementary Therapies journal, shockingly, found zero evidence to conclude the basis of any claims made by practitioners. In fact, you can test any claims for yourself with a small experiment, as I will do right now. As they claim that the magnet will affect your blood flow, placing a magnet on your skin will make the skin appear red as the blood will surely come to the surface, as they are attracting. I have placed a magnet on my arm, and on my lower leg. 10 Minutes later, I see no result. 30 Minutes later, I see no result. After an hour, every pain in my body from this cold has gone. THIS ACTUALLY WORKS. Oh wait, no. My mistake; absolutely nothing happened.

Law

The stall I saw had a website: www.magnetichealing.com which I was surprised to find has absolutely no information. It is essentially a place to find quick links to other websites, strange. If you were selling a product to people that you truly believed works, in the face of surmountable evidence, why would you not want to promote such products? Never thought I would be in support of homeopathy, but at least they stand on their own….merits? (I use that term for a lack of a better word, homeopathy has no merits).

In the early 2000’s there were numerous court rulings on practitioners making false claims about these products. As previously they were marketing magnets for cures, the companies marketing such products were sued and now use stupid phrases such as: ‘supports the healing process’ and the less glamorous ‘helps with’.

Not Medical Doctors…Then Who?

As I cannot find anyone to blame for the stall I saw today (other than the people working there, but I wasn’t going to ask questions in the middle of a Saturday afternoon in a busy shopping centre during the Christmas period. I’m not mental). I have found the website: biomagnetismusa.com which is a fascinating and riveting website aimed at people who haven’t an ounce of sense in their human body. Within this site, the author, Helana Guerrero, describes to the general public as to what magnetic healing actually is. Obviously using the classic pseudoscientific words as a marketing scam: Toxin, Detox, my favourite section is this:

“Virus and fungus live in acidic enviroment, bacteria and parasite alkaline. By placing magnets of the same polarity on each point, we push the charges towards each other and the area gets balanced, equilibrium is restore to a neutral pH, then pathogens instantly die since pathogens can not live in a neutral pH and we get rid ot them.”

That is copied and pasted as found, proof-reading is clearly not vital, then again, nor is fact-checking. One word completely defies this sentence: Homeostasis. This is the tendency of a system within a living organism (not always living) to maintain an equilibrium by reacting in regards to a stimulus. You should surely remember this from high school. This belief flies directly into the fact of our homeostatic biological nature. There is nothing really you can do, with the exception of what is essentially poison, to change your blood pH level. We have multiple feedback loops that have evolved through the ages to correct our pH level, magnets are not going to change that. You can’t easily affect blood pH, essentially, that is called poisoning. And that will obviously kill you. More on pH quackery can be found here.

Then we get to a better section, the disclaimer:

Helena Guerrero has been Certified to provide BioMagnetism Therapy by the El Centro de Investigacion de Biomagnetismo Medico, S.C.in Mexico, The University of Chapingo, Mexico and by Dr. Isaac Goiz Duran.
She is not a Medical Doctor, she is not making a medical diagnosis or providing medical advice or care.
You should see a Medical Doctor for medical care, and you should view BioMagnetism Therapy care as additional therapy to the medical care provided by a Medical Doctor.
Biomagnetism Therapy is not a substitute for Physician consultation, evaluation, or treatment.

Essentially reworded to: I’m not a medical doctor. This doesn’t work as a cure for anything. See a physician for actual care. At the end of homepage is a list of things that biotherapy apparently helps. It’s a long and amusing list, and its all thanks to Dr Isaac Duran, who has patented this biomagnetic treatment with absolutely zero evidence for it’s claims. Unfortunately the website doesn’t have a price list for how much it would cost for such a treatment to help with any ailments. Maybe if I get my head cut off one day I’ll visit for the cure, I’m sure magnets can fix that. 

Conclusion

Obviously it is frustrating to anyone with an ounce of scepticism, critical thinking and basic scientific knowledge, that people are falling for this and still forking money over to these shills. Of course, I would be wrong to have reviewed and questioned the science and practicality of this in the eyes of practitioners, they will claim that there is insurmountable evidence to prove the claims made. Who am I to argue with that? Oh wait, someone who actually knows what they are talking about and is not biased-ly trying to sell something. Either way, this remains a fringe science with only circumstantial testimonials as evidence. If you went for surgery and asked if a treatment worked and they said ‘well, Tom from Leeds says that I fixed him’ you’d be a little suspicious. Why not apply the same scepticism to people selling you magnets for cancer treatment? Read that last sentence again. Done.