04 February 2009

So breast cancer screening really isn’t worth it – but women aren’t told that.

Supports Chapter 2: What’s behind the screens?

There is another gem in the British Medical Journal.

Peter Gøtzsche and colleagues argue that women are still not given enough, nor correct, information about the harms of screening.

Three years ago, Peter Gøtzsche and colleagues at the Nordic Cochrane Centre, the Department of Nuclear Medicine, and the University of Copenhagen, Denmark, published a survey of the information given to women invited for breast screening with mammography in six countries with publicly funded screening programmes. The major harm of screening, which is overdiagnosis and subsequent overtreatment of healthy women, was not mentioned in any of them.

This latest analysis shows that nothing has changed. Although the information that women were given should have been about both the benefits and adverse effects of breast cancer screening, the supposed benefits were hyped up, but the harms were still not mentioned. The authors say:
“By contrast, little information is given about harms. It states that "some women" find mammography uncomfortable or painful, which becomes "many women" in the summary. The summary also notes that recalls for more investigations "can cause worry." No mention is made of the major harm of screening - that is, unnecessary treatment of harmless lesions that would not have been identified without screening. This harm is well known and acknowledged, even among screening enthusiasts. It is in violation of guidelines and laws for informed consent not to mention this common harm, especially when screening is aimed at healthy people. The new guidelines from the General Medical Council state: "You must tell patients if an investigation or treatment might result in a serious adverse outcome, even if the likelihood is very small." The likelihood of being overdiagnosed after mammography is not very small; it is ten times larger than the likelihood of avoiding death from breast cancer.”

“Another harm is false positive diagnoses. The leaflet notes that about one in every 20 women screened will be recalled for more tests, but does not explain that this 5% rate applies to only one round of screening. The rate of false positive diagnosis after 10 screenings was 50% in the United States and 20% in Norway.”
And there are many more examples of the harm that mammography causes that are mentioned in Chapter 2 of Trick and Treat.

Gøtzsche and co publish a specimen leaflet which does list both sides. It is this:

Summary from evidence based leaflet
• It may be reasonable to attend for breast cancer screening with mammography, but it may also be reasonable not to attend because screening has both benefits and harms

• If 2000 women are screened regularly for 10 years, one will benefit from the screening, as she will avoid dying from breast cancer

• At the same time, 10 healthy women will, as a consequence, become cancer patients and will be treated unnecessarily. These women will have either a part of their breast or the whole breast removed, and they will often receive radiotherapy and sometimes chemotherapy

• Furthermore, about 200 healthy women will experience a false alarm. The psychological strain until one knows whether it was cancer, and even afterwards, can be severe
But I doubt that women will be told the truth. If they were, they would probably say ‘no, thank you’ and doctors would then see a cut in their salaries – and that would never do, would it?

Gøtzsche PC, et al. Breast screening: the facts—or maybe not. BMJ 2009;338:b86


Anonymous said...

Not quite the same topic, but still relevant, I had a problem with cystic breasts a few years ago. My doctor told me I should stop drinking caffeinated beverages, which I did but the problem didn't change. One of the first 'side effects' that I noticed when I started LC was that these painful lumps were gone.

Back to mammograms, I haven't had one yet and as I don't have any risk factors, I don't really think I will get one. I can't imagine that squishing breast material like that wouldn't in itself cause some tissue damage.

Barry Groves said...

Hi Anon

If you had had a mammogram when you had the cysts, there is a chance that you wouild have also had a biopsy 'to be sure'. Biopsies cause inflammation, and inflammation has been shown to initiate a tumour. Biopsies also spread cancer cells if ther is a malignant tumour there.

You are also right about the damage that crushing the breasts can do.

I am delighted that the lumps disappeared when you started to eat a low-carb diet. That is a benefit I didn't know about.

Anonymous said...

This is exactly what happened to me. In my 40's, I succumbed to the pressure of getting mammograms. 1st couple were nothing, albeit quite painful. The 3rd said there were calcifications and they insisted I get a biopsy. Talk about abject terror! And the biopsy was excruciatingly painful. Absolute torture - Novocain doesn't work very well on me.

In my usual manner, I researched it and found that for a woman at that age with my history and profile, the odds of it actually being anything at all was over 600 to 1. 600 false positives and unnecessary surgeries (cost over $1500 for that procedure) to one actual problem! Mine was completely negative but they still tried to scare me into more treatment.

This isn't science! It is a scam. It is a terrible and inaccurate screening tool. I also learned that mammograms have a large number of false negatives too.

I thought there had been some studies showing that whether women get mammograms or don't, the mortality rate from breast cancer was the same.

I decided the risks (adding to the fact that not only are they painfully compressing gland tissue but they are also radiating it) were not worth it.

Barry Groves said...

Hi Anon

There are many studies which show that mammography is not only a waste of time and money, it also causes both physical and psychological problems. Many of these are in Chapter Two.

And so is my mother's case. She went into hospital with a hiatus hernia. It's hardly life threatening. But as she was there, they did a full physical and found a lump in her breast and biopsied it. It was malignant. A few months later she died of a metastasis in her liver.

Before she died, she told me that she had known about that lump for over 20 years. It had give her no problems.

In my opinion, the hospital doctors killed her.

Amanda said...

I was recently invited for a mammogram and, having read your book Barry, declined.

Caroline said...

I'm 65 and have always dutifully attended for mammograms when called. Six years ago, however, I had a recall letter after a routine screening and I will never forget the terror I felt while waiting for the appointment. After another mammogram and an ultrasound I was found to have benign calcifications and the relief was enormous, but three years later I was very nervous of returning for my next screening. I finally did go, after putting off the appointment several times, and it was found to be clear, but now the dreaded 'pushy' 'invitation' has arrived again. This time I am refusing to be bullied into this and after a lot of online research I have made an informed decision not to attend. My search for information led me here and I'm so grateful to have found this site. It reassures me that my decision is correct. I have also ordered a copy of 'Trick and Treat' while I am about it!

TW said...

I have just removed myself from the Breast Screening registry.
I'm afraid that I have never trusted the medical profession to tell us the truth - I do my own research.
I was shocked to get to the truth behind cervical screening - 1000 women need to be screened regularly for 35 years to save ONE woman! (Dr A. Raffles, cancer screening expert)
An unreliable test for an uncommon cancer means lots of false positives and lots of healthy women harmed by unnecessary colposcopy and biopsies - a few women are helped by this test, thousands harmed...

Now we have breast screening being pushed onto us - once again, the information provided is woefully inadequate and dishonest IMO...
False positives leading to anxiety, biopsies and/or surgery.
Also, new research that shows screening is likely to INCREASE the risk of cancer, they suspect because of the bruising of the breast tissue AND the dilemma of ductal carcinoma in situ (DCIS)- a slow moving cancer that 40% of older women will have...that is unlikely to ever bother them - once biopsied, it can become aggressive, once diagnosed, the breast usually comes off....(the Dr fears liability)
I think it's about time the medical profession was forced to tell us the truth about this testing - informed consent has been disregarded in a bid to recruit women and reach screening targets.
Did you know doctors are paid to recruit women into cervical screening and to reach screening targets?
How unethical to put targets first and totally disregard informed consent?
These payments have led to some highly unethical behaviour - women being harassed and pressured every time they visit a Dr for anything, women with complete hysterectomies for benign conditions being pushed into testing, (thousands of women are tested needlessly ever year) screening young women (very high risk of false positives and harm) women screened too frequently, (increasing your chance of harm) deliberately withholding any information that may deter women from screening, overstating the benefits of testing and exaggerating the risk of cancer.

I wonder what's next on the cash register - what other unreliable and harmful tests do they have that are essential to our health? Roll out the scare campaigns!

gerry said...

Hi Barry,
I got to your sites today from a link Jennifer McLagan sent me in an email, from my response to her book: "Fat: An Appreciation of a Misunderstood Ingredient."
I'm gradually working through your different topics: fat, climate change etc.
Just thought I'd stop here and say I reject all offers to screen/scan any part of my anatomy, or to receive jabs of any kind.

Barry Groves said...

Hi Gerry, and welcome

Jennifer McLagan and I had adjacent reviews in the Sydney Morning Herald last year. We share common thoughts on fats.

Your attitude to the machinations of the medical profession parallels mine. Although, that said, as at my age I don't want to alienate my doctor, I do let him draw half an armful of blood off once a year which, as it happens, allows me to show him that 'despite' my high-fat diet, all is normal.


Deborah said...

There has been increasing criticism made about the scant and misleading information provided to women about cervical and breast cancer screening.
The Nordic Cochrane Institute has taken matters into their own hands and released an information leaflet for women considering mammograms.
The UK Breast Screen attempted a redraft which was woefully inadequate.
I doubt a screening authority will ever give us balanced information - they want us to have screening and have made a practice of keeping the limitations and risks of testing from us and even denying the existence of serious risks.

In cervical screening, it's exaggerating the risk of this uncommon cancer and failing to mention the high risks of testing - an unreliable test leading to serious rates of unnecessary and possibly harmful colposcopy and biopsies for false positives.
Mammograms - failing to mention the risks of testing.
False positives, unnecessary biopsies, surgery and other treatment, the discovery of ductal carcinoma in situ and what to do about it (they're not even sure!) and new research that suggests mammograms may increase your risk of cancer due to radiation exposure and compression of breast tissue.
Thankfully, the push for greater honesty has arrived and doctors are being forced to respect a woman's right to choose.
We're not children and I resent being demanded to have screening with no information.
Only I can say the risks of testing are worth it and I need all of the risk information to make my decision....not scary ad campaigns or being subjected to tactics to force me into screening.
You'll find the new leaflet at:

Anonymous said...

Barry - can you remove the comment by Edward just above - he has inserted a link to a spam type website.

Barry Groves said...

Thanks anon for alerting me. Strangely, I didn't get an email telling me it had been posted.