Breast Screening - Some inconvenient truths - 28 Oct 2010
Tip: Highlight text to annotate itX
>> Mr. Chairman, ladies and gentlemen, first of all,
welcome from our founder.
This is Jeremy Bentham whose embalmed body is just
up the road for everyone to see.
He's head has got rather rotten,
so the head you see here's brought out on special occasions
which allows me to imagine what they're saying,
would I tell a lie, that's the plaster of Paris head.
His will has probably and that's the kind of relationship
that I have with the Department of Health over the issue
of breast cancer screening.
This is the miracle of San Carlos Borromeo,
a mid 17th century painting by Giovanni Crustini [phonetic]
and it refers to the miraculous healing of a breast cancer.
This is mid-17th century and you can see the terror
on this woman's face.
So the diagnosis of the suspicion
of breast cancer generates terror in the heart of a woman.
My family has experienced this terror.
This is me as a little boy and that is my beloved mother Mary
who died tragically young and in uncontrolled pain.
And her experience left me with anger.
This disease is upfront and personal.
And then about 15 years ago my baby sister Linda who was then
in her early 50s, she developed breast cancer.
But things had moved on again a lot since then
and thank God she's alive and well 15 years later.
But it's in the family.
I've got two daughters and my sister has four daughters.
[ Pause ]
>> Sorry about that.
Women invited to screening received these leaflets,
Breast Cancer: The Facts.
The object of my talk to you today is
to say this should be retitled Breast Cancer: The Fibs.
And it's not just me, some maverick saying this stuff.
There was a lead article in the British Medical Journal
in February last year Breast Screening,
What the Leaflets Don't Tell You.
I'm not alone.
And over the last year or two, the evidence has got worse.
The Journal of the Royal Society of Medicine the beginning
of this year, Has Breast Screening Save Lives,
a question mark.
The BMJ then published a review on the experience
in Denmark demonstrating breast cancer did not save lives.
Last month, there was a major article and an editorial
in the New England Journal of Medicine,
the most prestigious medical journal with the title,
Screening Mammography: A Long Run for a Short Slide.
And then also recently the British Medical Journal
commissioned Professor Klim McPherson
to independently review the data and he concluded the same
as the New England Journal of Medicine and Fiona Godlee
in her editorial supported the fact
that this subject seriously needs attention
from the Department of Health.
I want to highlight a table from the New England Journal
of Medicine editorial.
Now, read this carefully, estimated benefits
and harms associated with 10 years of screening
for 2,500 women aged 50 or more.
You avoid one woman dying from breast cancer
for every 2,500 screened for 10 years, that is the benefit.
Against that, a thousand women will have
at least one false alarm and will undergo unnecessary biopsy
and breast cancer will be over diagnosed in 5 to 15 women
who will then be treated unnecessarily for a disease
that would never threaten her life.
How can you understand this?
This is so counter
to the culture you've been brought up in.
Catch it early, save your life.
My answer to the question,
has breast cancer save lives is a categorical no.
Let us go back to the underlying hypothetical model
which drives the screening industry.
You start off with a lesion which we call ductal carcinoma
in situ, which is assumed
to be a precursor lesion for breast cancer.
Then that progresses to an early breast cancer which progresses
to a late breast cancer.
So very simple, simplistic linear dynamic.
So screening theory would have you believe, catch it early,
save a life and save a breast.
This is based on the premise that detection early,
by that I mean small cancers leads to a fall
in the incidence of late cancers.
The detection of in situ disease will prevent the development
of invasive disease, smaller cancers, fewer mastectomies,
fewer advanced cases, lower mortality.
None of that is true.
It is the assumption yet the scientific data refuse
that very seductive hypothesis.
To understand this, you need
to understand the biases associated with screening.
There are three biases: lead-time bias
where you're simply prolonging the period of observation,
length bias where you are simply picking up good cancers
and the bad cancers slip through, and attendance bias
which is a social class effect.
Let me explain that.
Here we have a timeframe from clinical detection
of breast cancer to either death or from cancer
or death from old age.
If you increase the timeframe to the left and pick the disease
up at screening, then survival is prolonged even though the
long-term outcome is the same.
And that's called lead-time bias.
Length bias is illustrated by this cartoon [inaudible],
the cancers, but [inaudible] intervals,
the moment that's 3-year intervals.
We catch the slow swimming fish in these intervals.
But the really nasty fish,
the sharks that are gonna kill you slip through the net.
And those are called interval cancers.
And even if you shorten the interval to a year instead
of 3 years, you get the same.
Attendance bias means attenders
who accept the invitation are different to those who fail
to accept the invitation.
Non-attenders, we know are lower social class and we know stage
for stage, lower social class women do worse with the outcome
of breast cancer for reasons we're not quite sure.
And there's nothing to do with access to treatment.
We don't yet understand that.
Because of these biases, the only way
to assess whether screening saves lives is randomized
control trials comparing a screened population
with an unscreened population
where the primary outcome is cost specific mortality,
not survival.
You count the number of women dying of breast cancer
in the screened against the unscreened.
But at the same time it is just possible
that all this activity might be detrimental for other causes
of death and therefore,
a secondary endpoint is all cause mortality.
>> The National Health Service Screening Program was
established in 1998 following the Forrest report.
This is Sir Patrick Forrest who was a good friend of mine
and I respected him enormously.
And it was predicated on the outcome
of seven randomized control trials which started
in the early '70s and were reported in the mid-'80s,
and that's very important thing to mote.
And the outcome of a summation
of those trials was a relative risk reduction
of breast cancer mortality of 25 percent which is another way
of saying a hazard ratio of 0.75.
I don't expect any of you to understand
that unless there are few statisticians in the audience.
But that 25 percent is what the women get.
None of them can really understand it
because it's framing of a result which I will explain shortly.
I was given the task of setting
up the first National Screening Center in the UK
when I was Professor of Surgery at Kings
and I chose Camberwell Green and we set up this clinic.
We were given a year from the Forrest report to get up
and running and start training everybody
to do screening in 1998.
I know about screening.
I started it in the Southeast of England.
Within 8 to 10 years, it all went pear-shaped.
There were 2 sets of reports that looked
at the more mature followup of these clinical trials
and also looked at the probity of these clinical trials.
And reports started to come
out in all the top journals demonstrating the initial
estimate of a 25 percent relative risk reduction was a
gross overestimate.
So, the NHS Screening Program was predicated on 25 percent.
The United States Preventative Services Task Force both in 2002
and again in 2009 said it's not, it's 15 percent
and the Cochran report, Cochran is an independent group based
in Denmark who take on subjects for overview analyses
and they derive the same percentage.
So screening is associated
with a 15 percent relative risk reduction
but these are the old trials that were started
in the mid-'70s and reported in the mid-'80s
since when treatment has improved.
Here is one illustration of how treatment has improved.
At the time these trials were being conducted,
the 5-year survival for breast cancer in the
over '50s was about 70 percent.
In 1984, '85, we had the first overview of trials
of adjuvant Tamoxifen and immediately,
the 5-year survival showed up to 85 percent.
And now with newer drugs,
and I won't bother you with the details.
We now expect a 90 percent 5-year survival compared
with the 70 percent 5-year survival
at the time the trials were being done.
So, in other words the window for improvement
from screening gets narrower and narrower.
Now this is tough, a tough table but it's
to give you an idea how we translate these relative risk
reductions in to absolute numbers.
Don't be embarrassed if you can't follow it.
Trust me or turn to a neighbor who happens
to be a mathematician.
So, we take 10,000 women, age 50,
and we screen them for 10 years.
The incidence of breast cancer in this age group
of women is 2,000 per year.
So, this group of women will generate 200 breast cancers.
With modern treatment, over 10 years,
this is a medium followup of 5 years.
So it's a medium follow up of 5 years for this group of women
with modern treatment who would expect 20 deaths.
The relative risk reduction is of the number 20.
So a 25 percent reduction
of the number 20 means the absolute benefit is 5.
Five breast cancer deaths avoided over 10 years
when you screen 10,000 women.
But if the figure is nearer to 15 percent,
it is 3 breast cancer deaths avoided
by screening 10,000 women for 10 years.
This leads to the issue of the framing of the result
where we now just got numbers needed
to screen to save one life.
If we take the initial NHS estimates,
it works out at 1,000 women for 10 years
to avoid one breast cancer death.
If we take the more recent estimates,
based on the same trial data, you have to screen close
on 1,500 women for 10 years to avoid 1 breast cancer death.
But if you take the modern era
and this is what the New England Journal of Medicine referred
to where treatments are so much better then you have to screen
about 3,000 women, two and a half to 3,000 women for 10 years
to avoid 1 breast cancer death.
And that's called framing the results.
How can you expect women invited for screening being told
that that is the case
to understand how disingenuous that invitation is?
Muir Gray was the Director of the National Screening Program,
an honorable man and he wrote all screening programs do harm.
Some can do well, too good as well as an afterthought.
And that is the issue.
The downside of screening are false alarms, over diagnosis,
unnecessary surgery, an increase
in mastectomy rates, not decrease.
I want to say a little bit about over diagnosis.
Here is a histopathological picture of ductal carcinoma
in situ and it is assumed that it will inevitably progress
to invasive breast cancer if you don't adequately treat it.
Well, that is simply not true.
And the estimates from the Cochran report are
that for every breast cancer death avoided, 10 women are
over diagnosed and over treated
for something labeled breast cancer
which does not behave like breast cancer.
Shocked, horror, because I dare say that in public,
people use ad hominem attacks, he must hate women.
He's a misogynist, he murders women.
And yet, the same is exactly similar
for prostate screening trials.
Again, in the New England Journal of Medicine last year,
the outcome of the prostate screening trials
that for every prostate cancer death avoided by PSA screening,
50 men are over diagnosed and over treated.
Everyone accepts that.
I don't know why.
Is it double standard here?
They accept that men are over diagnosed by screening
but they are resistant to the notion that women are
over diagnosed as a result of screening.
In the year 2000, Michael Douek, a surgical colleague of mine
and myself, we looked at the cancer registries
and plotted the incidence of ductal carcinoma in situ
since the introduction of screening in the London area.
The blues and the yellows are the group not screened.
This is the group that is screened.
This is the increased incidence in ductal carcinoma in situ
from less than 500 a year to nearly 2,000 cases a year
in the London District.
What we assume based on screening theory,
the knock-on effects of that would be the invasive cancer
would stop fully.
Well, this is what we saw for invasive cancer,
the unscreened blocks, the screened blocks,
and it wasn't the case.
The incidence of invasive cancer also goes up.
So in situ cancer, uninvasive cancer go up in parallel
when you start screening a population.
And that is over diagnosis.
And it's not just us mavericks, these was a separate analysis
by Joregensen published in the British Medical Journal.
>> This shows the incidence of breast cancer in those too old
to be screened and the green, too young to be screened,
and this group in the middle, this was the incidence
of breast cancer before screening,
and this is invasive breast cancer.
Note, it shoots up to the same incidence as the elderly women
and remains up once you introduced screening and that's
when they introduced screening for the 50 plus,
and then if you follow that down to go to another 10 years
and here we look at the older age group who've been invited
to the screening, the same thing happens, and this is repeated
in every country in the world.
The introduction of screening increases the incidence
of breast cancer by closed on 50 percent increase and 20 percent
of those are in-situ cancer.
This is what we discovered looking at mastectomy rates.
Mastectomy rate shot up since screening started.
This is the ductal carcinoma in situ
and that was 10 years ago, those results.
Michael Dixon in breast cancer research last year has looked
to the last 10 years, again, showing the incidence
of in-situ cancer shooting up and the incidence
of mastectomy shooting up.
In every country in the world that introduces screening,
mastectomy rates go up.
Here is a summary slide of what I have said,
and note it was published 5 years ago
by Barrett in the BMJ 2005.
Working up from the bottom, this is breast cancer deaths,
caused specific deaths in the screened and in the unscreened.
This is breast cancer incidents in the unscreened,
this is the breast cancer incidents in the screened,
and this, these two lines
that are superimposed are total mortality, and again,
in all the slides-- all the trials, all the summation
of all the trials, there is no effect on all-cause mortality,
and yet the women are coerced to attend the screening
without informed consent even to the point that they coerce women
with learning difficulties, I find this disgusting.
It's meant to be a cartoon of a woman with Down syndrome
and when you open the page, you will see a cartoon strip trying
to persuade this women to come for screening,
and the irony here is the women
with Down syndrome almost never get breast cancer,
and then you come back to Breast Screening: The Facts,
and this is the leaflet my wife got two to three weeks ago.
Breast cancer, the spin, look at this.
Around half the cancers that are found
on screening are still smaller enough
to be removed from the breast.
This means the whole breast does not have to be removed, hurray,
only 50 percent mastectomy rate.
And yet, for clinical breast cancer found
in the normal way is only 25 percent mastectomy rate.
You have twice the risk of having a mastectomy.
If your cancer is screen detected
but we mustn't tell the little women.
It might frighten them off, and then they come
up with this figure,
breast screening saves 1400 lives a year.
I don't know where that number comes from, honestly.
Hand on heart, again and again, myself and my colleague,
where and how do you derive that number.
We get no answer to that question.
As far as I am concerned, it's a made-up number.
On the basis of this, I resigned
for the National Health Service Screening Committee just
over 10 years ago and I wrote a letter to the Lancet explaining
to the medical establishment what I had explained to you.
And what happened, every doctor
in the country got a glossy leaflet like this.
This is a photograph of it, ridiculing me and worst of all,
this chart here, let me magnify it.
They published this table to demonstrate
that breast cancer mortality was going up and up and up,
and then screening kicks in and it fell down.
That is scientific fraud.
If I published that, I would be
up before the General Medical Council.
It is fraudulent.
This is the truth and this comes from CRUK,
nothing to do with me.
Breast cancer mortality reached the peak
in all age groups in about 1987.
1986-'87 was the time adjuvant systemic therapy was rolled
out for all women.
Tamoxifen, chemotherapy which has had an effect on mortality
of 30 or 40 percent reduction but note,
this fall in mortality is in all age groups,
not just the age group being screened.
So any fall in mortality we're seeing is due
to improved treatment not due to screening.
I am not suggesting we shutdown screening.
First of all, it would be political suicide
for any government to do that but I have been invited.
I was invited last year to speak to the Science
and Technology Committee at the House of Commons
to explain what I would do about this,
and I had a very warm reception.
What I recommend is that instead of blanket screening
for the whole female population,
we should have a risk assessment,
risk management campaign rather than one size fits all.
This is just the picture of one
of the modern algorithms how we can accurately predict risk
of developing breast cancer both from family history,
demography, and so on.
And as a result of that, it is possible
to carry out the triage.
If we look at the low-risk group,
these women have something like 50 times the risk of dying
of cardiovascular disease and breast cancer.
Why are we obsessed by one issue?
Perhaps this group could be advised on how
to avoid cardiovascular disease, stop smoking, healthy diet,
avoid alcohol,
which incidentally might reduce the risk of breast cancer.
This group at the top end--
genetic counseling and genetic testing.
Maybe if we just screen the middle risk group,
we might have more bangs for the buck and talking
about buck we're talking 70 million pounds a year
on this thing, who knows.
So maybe it would be rational to adopt a program like this rather
than continue to coerce innocent women with half truths
to tick boxes and fulfill targets.
If nothing else, you will agree with me it is shameful
and disgusting that women are denied the opportunity
to learn the truth about screening.
So my conclusion is treat women like adults,
offer informed choice rather than political spin,
and I think the message might be getting through because I saw
in the Evening Standard a couple of weeks ago,
the London Clinic is offering mammography at a reduced price.
They can no longer sell it, damage goods.
Thank you very much.
[ Applause ]
>> Thank you Professor Baum.
That was thought-provoking and fantastic.
Can we please start to have lots of questions?
Okay. We have a microphone coming in so
if you could use the microphone please.
>> You did say early on that detected early,
the new treatments will have a greater chance of success.
[ Inaudible Remark ]
>> What-- sorry?
>> I didn't say that.
I'm sorry.
>> I thought you did.
>> No, I said that was a theory, catch it early.
It is a theory.
My problem is the catch it early mantra is something of a cliche.
What people are saying is catch it small,
and the way I teach my medical students on this is
if you are a woman and you have a 1 centimeter cancer,
would you rather it was six weeks old or six years old
and the answer is you'd rather it was six years old.
>> Right. What sort of-- I don't know how I'd ask this now.
What sort of detection should someone
in my age group, 70 now and getting--
>> You don't look 70, come on.
>> I am. Thank you.
[ Laughter ]
>> You don't look old enough to be screened even.
>> But I'm in an age group
where it is theoretically increasing even
on your charts there.
What should I do?
>> Right. That is a very sensible, excellent question,
and I'm often asked that,
and the answer is you don't do anything.
And the reason you don't do anything,
the results you'll see fantastic improvements with treatment.
These are women who by chance detect the breast cancer.
Having detected it by chance then they're aware they should
go and have it attended to,
but you don't live your life worrying about breast cancer.
If you want to worry about the most likely cause of your death,
worry about cardiovascular disease.
Do not obsess about breast cancer.
[Inaudible] more likely to die of cardiovascular disease.
I hope you don't smoke.
[ Inaudible Remark ]
>> Michael, as you know because we consulted you,
my wife recently had a breast cancer, and the biopsy showed
that it wasn't [inaudible] but invasive lobular so,
and 2 centimeters and that's--
despite the fact that I've signed the letter with you
about the inaccuracy of the NHS information
which is undoubtedly the case.
I think [inaudible] the thought I must say.
Would you like to comment?
>> Yes. Yes.
That is often the killer question because you do not want
to be unkind when you answer it.
Now, I don't have to be unkind in answering your question
because it's-- the message is good news.
It's all good news.
There are two possibilities: left undetected
that might not progress or it would not progress
in the woman's lifetime,
the woman's normal expectation of life.
I left out a whole section on the natural history
of breast cancer where untreated many breast cancers,
clinical breast cancers don't do any harm
so that's one possibility,
the other possibility might even regress spontaneously,
or the third possibility, she-- we're talking about your wife.
[ Inaudible Remark ]
>> I know.
The other possibility she may be that 1 in 2500 women.
So whichever way you look at it it's good news.
>> Diane [phonetic], I think there were two people
with their hands up here, okay.
Here. Alright.
>> Late in your presentation you were talking
about risk assessment triage and your slide suggested
that there were some software that did that.
What is that software called please?
>> Well, that is-- there are several versions
of that software.
That's the IBIS 2 software, which was developed
in Saint Bartholomew's Department,
Professor Jack Cuzick's department is IBIS 2.
There are others that are coming online all the time.
We are working towards having an iPad technique
where the patients, or not patients, the clients,
where the clients can fill in all the data on an iPad
which is instantaneous,
translated into a risk before coming in to see the doctor.
So, the technology exists, in fact that technology
for risk assessment, the iPad or touchpad actually sat
in a clinic, Massachusetts General recently
and they've already got that going and I
like to get that into London.
>> We have a gentleman here.
>> Okay. Suppose you had an extra hour of teaching available
for medical students, would you teach them about cancer
or would you teach them about numbers needed to treat?
>> That is a very easy question.
What I have described to you is
of generic issue illustrated by breast cancer.
It applies across the board.
The first thing our medical students must learn is a degree
of numeracy and an understanding of risks,
and I wish they'd learn this in their first year.
Is that the right answer, sir?
[ Inaudible Remark ]
>> Thank you.
[ Laughter ]
>> We have a gentleman down there.
>> Yes. You have spoken always with reference
to mortality rate, death rate.
Would any of your conclusions be different if you're concerned
about quality of years lived?
>> Quality adjusted life.
Well, I mean, that is an excellent question.
Quality adjusted life here is you cannot supply
in health economics unless you can demonstrate years
of life per se.
Quality of life though is a real important issue.
Now some of these women, I've written a lot
on the natural history of breast cancer
and I've collected a large series
of clinically avert untreated breast cancers,
and they're pretty grotesque.
What happens to them even if they're not killing the woman,
they're horrible and they impair quality of life
so there is an argument for the local treatment in any case
to maintain a good quality of life but that isn't an issue
with screening because if you allow the minority screened
detected lesions to progress to become clinically detectable,
these days they're very easily treated.
Local treatment now is adorable, it's minimalistic,
and it's getting more and more minimalistic as we go.
>> We have a lady in there.
>> Thank you.
Given that the government is now even more committed
to saving money where it can in the NHS,
I wonder is it too optimistic to think that the logical proposal
from you presented, which is the government could save money
by doing much less screening, use a fraction of that savings
to set up the screening and prevention trials
for the intermediate risk group and put some of--
the rest of the savings into improving access treatment
to the new drugs, and I could imagine that might go
down quite well and no one would have
to lose too much face about screening.
>> You are absolutely right, and I have been battling this one
for a number of years.
I do not want to embarrass the Department
of Health whichever government here.
I don't wanna embarrass them or humiliate them
but they won't listen.
I've been banging on about this for 10 years
and suggesting alternative ways of spending.
They simply will not listen.
We have a letter in the Times;
in fact Hazel Thorpe [phonetic] was the first author
of that letter in the Times.
Was it last week, Hazel?
A letter in the BMJ drawing attention to the fact
that in February 2009, we publically described
in the Times and the BMJ
that the leaflets were misleading,
frankly disingenuous.
Mike Richards, the cancer czar, responded two days later saying
that they are already working on an update, more honest report.
We haven't seen it yet, so we published a letter in the Times
to last week saying where is it, what's happened.
Meanwhile, 3 million women are being invited.
Is that the right number?
Three million women are being invited to screen
without informed concern.
So, I don't know what to do.
I'm just hoping a public lecture like this
which may cause ripples and get out to a lot
of audience may just embarrass the government
into doing something.
>> Thank you.
We have time for one last question from the lady
at the back and just to reassure you,
the lecture is being recorded
and it does reach a very wide audience,
so we thank you for this.
>> So I can kiss my [inaudible] goodbye.
[ Laughter ]
>> I have a more fundamental question, I am not very familiar
on how is this breast screening.
So, how safe is it like if you say that the breast is a system
and you disturb it by irradiating or something
like that, you may actually produce cancer
with over screening?
>> You mean by the x-rays?
>> Yes.
>> Yeah. The dose of x-rays
for mammographic screening is incredibly low
and less than the chest x-ray.
It's used to be a concern in the early days of mammography.
It isn't really a concern
that mammographic screening will induce new breast cancers.
By putting it another way, the "commonest cause"
of breast cancer screening"
because once you start screening the incidence goes
up by 50 percent.
That is, of course, it isn't causing directly the breast
cancer, it's exposing latent disease 'cause I don't think you
need to worry about the dose of radiation.
>> Okay, I think that we need to close
because there is a class coming here.
Thank you all very much for coming.
Remember to come back for next Tuesday, and this is fantastic.
This is exactly what the lunchtime lectures are all
about, free debate on interesting
and controversial subjects.
Thank you, bye.
[ Applause ]
