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Paracetamol, Prostate and HIFU, Uncertainty - Oxygen and Heart Attacks

Evidence suggests paracetamol is neither as effective or safe as previously thought for chronic pain. And is giving oxygen in heart attacks a help or hindrance?

Evidence suggests Paracetamol is neither as effective or safe as previously thought for chronic pain; Prostate cancer and new targeted treatments with fewer side effects plus feedback following last week's special edition; And is giving oxygen in heart attacks a help or hindrance? Margaret McCartney and Carl Heneghan debate the first in a new mini-series investigating uncertainty in medicine.

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28 minutes

Join us in the 麻豆社 Radio Theatre in London on 8th February 2017!

麻豆社 Radio 4鈥檚 Inside Health is hosting a special debate on the current state of the NHS. Dr Mark听Porter and guests discuss what needs to give.

The last few months have seen the service creaking under unprecedented demand, and there is likely to be worse to come.听 Something needs to give. Is it simply a matter of more resources, or do we also need to change our expectations of what the NHS provides? Is rationalisation and rationing the way forward?听

Mark is to discuss the issues with a panel including regular contributor Margaret McCartney GP, Claire Marx, president of the Royal College of Surgeons, and Chris Hopson, chief executive of NHS Providers.

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Submit a question for the panel by following the links below or on the 鈥楥ontact Us鈥� tab above

Programme Transcript - Inside Health

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THE ATTACHED TRANSCRIPT WAS TYPED FROM A RECORDING AND NOT COPIED FROM AN ORIGINAL SCRIPT.听 BECAUSE OF THE RISK OF MISHEARING AND THE DIFFICULTY IN SOME CASES OF IDENTIFYING INDIVIDUAL SPEAKERS, THE 麻豆社 CANNOT VOUCH FOR ITS COMPLETE ACCURACY.

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INSIDE HEALTH

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Programme 2.

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TX:听 10.01.17听 2100-2130

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PRESENTER:听 MARK PORTER

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PRODUCER:听 ERIKA WRIGHT

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Porter

Coming up today:听 Two stalwarts of the medical world go under the Inside Health microscope.听 Paracetamol - once the first line painkiller for most common ailments, its role recently has been questioned. We look at the evidence behind its fall from grace.听 And oxygen - widely used in all sorts of medical emergencies, but does it help, or does it hinder?

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Clip

Yeah that airway when people are having a heart attack I was drummed into, as a medical student, you give them oxygen, that sort of makes sense.听 The problem is when you look at the data on oxygen you can be making the situation worse and that goes counterintuitive to everything that I learnt as a medical student.

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Porter

Professor Carl Heneghan and Dr Margaret McCartney question its use in people who have had heart attacks, as part of a new series on uncertainty.

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And, and after last week鈥檚 special on prostate cancer, we will be continuing the theme with a report on two new techniques for treating the disease, and putting some of your feedback to one of the UK鈥檚 leading urologists.

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But first an appeal for your help with a debate that we鈥檙e planning on the state of the NHS. The last few weeks have seen the service creaking under unprecedented demand, and there is likely to be worse to come.听 Something needs to give. Is it simply a matter of more resources, or do we also need to change our expectations of what the NHS can provide? Is rationalisation and rationing the way forward? We are inviting a panel of experts, with differing viewpoints on the current pressures, to debate the issues and we are keen to hear what you think.听 You can get in touch by emailing insidehealth@bbc.co.uk.

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Paracetamol has had a remarkable career. First discovered at the end of the 19th Century it has long been the first-line painkiller of choice, but in recent years its role has been increasingly challenged by growing evidence that it鈥檚 not that effective. Evidence collated by researchers like Professor Andrew Moore from the Pain Research Unit in Oxford.

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Moore

Well for years paracetamol鈥檚 been the go to medicine in all sorts of different pain conditions and it figures in a whole pile of guidelines and recommendations in this country with NICE.听 To put it in perspective we use about 6,000 tonnes of it a year in this country.听 The thing is that what we鈥檝e discovered, because there鈥檚 been some beautiful large, high quality clinical trials done in the last few years, is that by and large for chronic pain conditions like low back pain and arthritis it either does not work at all, that is you cannot distinguish it from placebo, or that it works on a statistical level but the degree by which it is working is extremely small.听 So that would probably mean somewhere between about one and five people out of a 100 getting good pain response.听 That means the other 95-99 are probably not going to get any pain response at all.

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Porter

Margaret McCartney鈥檚 in our Glasgow studio. Margaret, as a practising GP like me, we have got used to offering paracetamol as a relatively safe first line treatment for lots of types of pain.

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McCartney

I think that鈥檚 true.听 We often think about paracetamol as the least toxic of a toxic bunch of medications.听 We often think of it I think as something that鈥檚 reasonably safe and has a reasonably good chance of working.听 But as Andrew says if that鈥檚 not the case and you鈥檙e giving someone medication that is not improving their pain all you鈥檙e doing is offering the risk of side effects.听 But they will work for some people and the problem that I often find is that because people鈥檚 pain is variable it can be hard sometimes to work out whether a painkiller taken regularly is actually doing you more good than a placebo would do.听 And that鈥檚 why I think we need to be much more open about the possibility that perhaps your painkiller isn鈥檛 working very well for you and perhaps we鈥檙e better taking nothing at all, perhaps you would have got the same effect from a placebo tablet.

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Moore

The one thing I would say is that when you work in the area of evidence for a period of time, particularly in pain, it makes you very humble because you can sometimes have a situation where you鈥檝e actually got nailed down evidence that a drug doesn鈥檛 work in a particular condition and then you鈥檒l talk to one of your clinical colleagues coming in from a clinic who said 鈥� look I鈥檝e had two people this morning for whom this is the only medicine that has ever worked in a 10 year experience of chronic pain.听 And so there will always be a small number and that鈥檚 the point, sometimes it is a very small number.听 But that鈥檚 the difference between saying this is the medicine you use first or this is the medicine you use last.听 And I think that鈥檚 the difficulty and which is why some people find the evidence around paracetamol quite challenging frankly.

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McCartney

Yeah and I think it鈥檚 really useful to think about it 鈥� you have evidence in terms of what works best for this group on average and what works best for this individual that鈥檚 in front of me.听 But it鈥檚 hard to work out who they鈥檙e going to work for in advance, which means that you鈥檙e having to try them on more people than they鈥檒l actually work for.

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Porter

Andrew, let鈥檚 look at low back pain, very common problem, if we鈥檙e not using paracetamol what should we be using?

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Moore

That鈥檚 a very good question.听 I mean one of the things I鈥檇 like to do, as somebody who has spent the last 30 years looking at evidence and pain, is I鈥檇 like to be able to say to you look there鈥檚 a mass of information I can give you which says that we should be doing this, this or the other.听 I can鈥檛 do that because the trials just are not there.听 We do know that in chronic low back pain the drugs that have been trialled in good clinical trials, there are two essentially, duloxetine which is an antidepressant and etoricoxib, which is an NSAID, and those are the only two drugs that I know of for which we鈥檝e got good data.听 Many of the things that are used, things like paracetamol and codeine, for example, or other paracetamol and opioid combinations, which are widely used in these conditions, there鈥檚 no evidence for at all.

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McCartney

One of the problems that you have is, as Andrew says, if we鈥檙e telling people that this doesn鈥檛 work for a lot people well what are you going to use instead.听 And certainly for back pain, things like physiotherapy can be very helpful, heat can be very helpful, sometimes anti-inflammatory rubs or gels can be quite good, they tend to be less absorbed into your body compared with the tablets, so there鈥檚 a reduced but not zero risk of side effects.听 So those kind of things can help but the older you are, the more other medications you鈥檙e on, the more interactions with other drugs there are, the more side effects you鈥檙e likely to get.听 So I think caution is definitely warranted.

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Porter

Is it still as safe as we thought it was?

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McCartney

Well it certainly is still safe overall and it is one of the safer drugs that we have but the problem is if you鈥檙e prescribing it with no benefit all you鈥檙e going to get are the risks.听 And the risks are small but they do exist and of course the more you use something the more likely you are to start to see even things that are a small risk in your population at large.听 So we鈥檙e talking about really particularly liver dysfunction, liver being under strain because of taking so much paracetamol and sometimes even very rarely liver failure, even as a result of taking paracetamol in normal prescribed doses, as in not in an overdose situation.听 It鈥檚 very rare but it does happen.

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Moore

I would add to that actually that maybe Margaret鈥檚 being a bit optimistic.听 There have been studies which have looked at paracetamol in more detail than we鈥檝e ever done in the past and what it actually is saying that in terms of its adverse event profile it鈥檚 not really very much different from ibuprofen.听 So I don鈥檛 know where the benefits are coming from.

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Porter

Andrew, let鈥檚 just be clear, we still think that paracetamol has a role in managing short duration pain of a variety of causes.听 Here we鈥檙e talking about longer term pain.

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Moore

That鈥檚 about right.听 I mean paracetamol鈥檚 not as good as some other things you can take if you have a headache, for example, or particularly in things like post-operative pain.听 But it works in a reasonable number of people, maybe about 25% of people for acute post-operative pain and maybe 10% of people with headache.听 And there are ways of getting around it.听 Paracetamol is extremely useful to put in combination.听 So when I get a headache I take 200 milligrams of a fast acting ibuprofen, 500 milligrams of paracetamol, together with a strong coffee.听 That鈥檚 because caffeine helps enormously in this situation.听 And I find that works extremely well.听 And all of that is nicely packaged in some beautiful evidence.

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Porter

Professor Andrew Moore with his insider鈥檚 tip on mixing over-the-counter painkillers to get the best effect and he should know.

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Last week鈥檚 Inside Health special on prostate cancer prompted many of you to get in touch and we put some of your comments to one of the main contributors to the programme, Mark Emberton, Professor of Interventional Oncology at University College London.

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Emberton

I鈥檝e seen a lot of patients since the programme and they loved it.听 I thought it would be a little bit too complex but actually no they liked the detail that you went into.

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Porter

Well you say that but it seemed to raise as many questions as it answered but of course that鈥檚 the nature of prostate cancer and the uncertainty that surrounds so much of its diagnosis and treatment.听 There was a lot of interest in conventional ultrasound guide biopsy missing cancers and one listener wondered about the TURP operation.听 He had to bore out his enlarged benign prostate.听 He said 鈥� given the scrapings were sent away for analysis would they be a reliable guide to whether his prostate was cancerous or not 鈥� because that鈥檚 a form of biopsy?

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Emberton

So the TURP typically we do for enlarged prostates where we don鈥檛 think is cancer is present.听 And the procedure basically removes the apple core of the apple and makes men pee more easily.听 Now we look at that tissue very carefully but that鈥檚 not typically where cancers originate from.听 And so whilst it tells us that there鈥檚 no cancer within that tissue it doesn鈥檛 provide the reassurance that this man is after.听 But a low PSA after a TURP would be very reassuring.听 If there鈥檚 any doubt at all we鈥檇 tend to let the prostate settle down for a few months and then do an MRI.

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Porter

We also mentioned, of course, the results of the Protec study which found no difference in outcomes in men who opted for active surveillance compared to surgery and compared to radiotherapy. 听But one listener was wondering about brachytherapy, this is a form of radiotherapy that he had, is that lumped in with radiotherapy, is it equivalent to the rest?

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Emberton

There are many ways of delivering radiotherapy.听 The Protec study could only do one, which was external beam radiation therapy, listeners will have heard of proton beam therapy, which got into the news last year, brachytherapy is another way of getting the radiation into the prostate.听 They鈥檙e all considered to be equivalent in terms of their ability to control the disease.

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Porter

We also spoke a lot about clinically significant disease and that MRI鈥檚 better at detecting it than ultrasound guided biopsy.听 One listener asked us to clarify what we actually meant by clinically significant.

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Emberton

You鈥檙e smiling, as I am, because this is a difficult one.听 This is disease we know is significant when we see it.听 So typically a bulky cancer that we can feel or indeed see on MRI that is high grade.听 In other words more like the tiger versus the pussy cat.听 So there鈥檚 a disease out there that we could all identify as being important in that if left untreated it is very likely that that man鈥檚 quality or quantity of life will be diminished.

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Porter

So by clinical significant what you鈥檙e saying is this is a potential threat to the wellbeing of the man and we need to do something about it?

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Emberton

Exactly right.听 And this is disease that is typically of increased volume, so in other words big, and high grade.

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Porter

One of the key messages to come out of last week鈥檚 programme was that advances in MRI mean we are now much better at determining where cancer is within the prostate, raising the possibility of a new generation of targeted treatments. So, instead of irradiating or removing the whole gland, you just treat the part with the cancer 鈥� hopefully reducing the risk of side effects like incontinence and erection difficulties.

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Killing tumours with high intensity focussed ultrasound (HIFU) is one such technique that is currently being trialled at Southampton General Hospital. I went to see consultant urological surgeon Tim Dudderidge to learn more.

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Dudderidge

The prostate gland, I鈥檓 holding a small model here which is probably about 50 cubic centimetres in size and this is a 3D rendered model of an MRI scan of someone鈥檚 prostate.听 And you can see that the tumour in this particular case may be between one and two cubic centimetres and this is a fairly small tumour that one might consider suitable for HIFU treatment.

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Porter

So it鈥檚 like a small pea in the middle of a plum.

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Dudderidge

That鈥檚 right.听 So when I see people with these kind of findings, as I was doing this morning, you go through the different options and this is a means of treatment that involves heating up the prostate and that鈥檚 done using this probe here, which produces ultrasound which is focused.听 And that heat energy is concentrated in a small area about the size of a grain of rice and that focal point will get to about 80 or 90 degrees Centigrade.听 Now obviously the prostate is bigger than a grain of rice and so when you鈥檙e planning this treatment you have ultrasound images which you capture using the same device and you can plan on the screen where you want to treat.听 And so originally we were treating the whole of the prostate but we realised that actually this is a much better technology for just partially treating the prostate.听 And so you would plan out the areas based upon your understanding of where the cancer is, based upon the imaging, and that will enable you to ablate the tumour and the surrounding area and avoid important structures like the urethra or sphincter, the bladder and the neurovascular bundles.

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Spranger

My name鈥檚 Howard Spranger, I was diagnosed with prostate cancer December 2014.听 For a couple of years before I鈥檇 sort of had trouble going to the loo sometimes in the night.

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Porter

Getting up for a pee.

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Spranger

Yeah, yeah and I did recall my father once having to have an ambulance to take him away because he had a similar problem.听 And I just thought it was a family trait.听 And 鈥� but I got it checked out eventually and it was kind of inconclusive.听 I suppose at the back of my mind there was always the possibility that it might be a cancer in the prostate.听 But you don鈥檛 want to think that way and nothing led to it really at that time.

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Dudderidge

Howard鈥檚 PSA was rising and at that point we felt it was necessary to get an MRI scan.听 In his case the MRI scan showed an area on one side of the prostate which appeared to be abnormal.听 And at that time it was my practice to do mapping biopsies of these cases.听 And those biopsies really identified that the disease was only on one side, matching up with the imaging findings, and then that led us into a conversation about his options really between focal therapy or between having surgery or radiotherapy.

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Spranger

The surgery to remove the whole gland 鈥� it felt to me like overtreatment but that was just because all I knew was that the cancer was fairly localised.听 And it was a big thing to go into as well, the potential side effects 鈥� incontinence and impotence really was what it boiled down to, neither of which prospects were particularly appealing.听 And I鈥檇 already been briefed on HIFU, I鈥檇 been told about it.听 The fact that it was not surgical just appealed to me, I mean I鈥檝e a fairly technical background and it was something I thought yeah this is a good novel new way of doing something and the least worse option, if you like.

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Dudderidge

Now as a general rule when we鈥檙e treating the prostate what we鈥檙e trying to do is trying to obtain lower side effects than you get with surgery, so this is the main advantage 鈥� you want to not have any incontinence, not have any erectile dysfunction.听 And so whilst we鈥檙e treating half the gland you might treat one of the nerve bundles but we know that by completing untreating the other side most people will have normal erections afterwards.听 And so what we find is about quarter of people may need to use a Viagra or one of these drugs afterwards but only one in 20 probably don鈥檛 have erections despite that.听

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Porter

So how do you actually operate 鈥� presumably the patient鈥檚 lying on their back, this probe goes into the rectum, up their bottom effectively鈥�

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Dudderidge

That鈥檚 right.

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Porter

And then that gives you the pictures that you鈥檙e looking at.

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Dudderidge

So we start off by bringing the patient into the operating theatre under an anaesthetic.听 We put the legs up so we can access the perineum and the probe goes into the back passage, it鈥檚 got lots of lubricating jelly and that makes a good contact for the sound energy to travel through.听 We then take some images of the prostate and then we mark it out in three different areas typically 鈥� the front, the middle and the back 鈥� and these areas overlap so you don鈥檛 get any gaps in the treatment.

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Porter

But the idea effectively is to leave as much healthy prostate tissue as possible and the surrounding structures, like the nerves, untreated?

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Dudderidge

That鈥檚 correct.听 And so the degree to which you do that is something that鈥檚 of interest to us because we might be able to bring it closer and closer to the lesion, the more and more confident we are that we know where the lesion is.

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Porter

And how long does the procedure take?

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Dudderidge

You鈥檙e talking about two hours in theatre.听 So we normally do four cases in a day.

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Porter

Of course the big difference between this procedure and removing the gland completely is the cancerous tissue is potentially still inside the patient, you hoped to have killed it but do you know for sure?

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Dudderidge

So I鈥檓 someone who does surgery and I do focal therapy and so I鈥檓 often torn with this situation where somebody who on paper is somebody who could be a candidate for a trial.听 We have very rigid trial inclusion criteria.听 So I no longer have to worry about it myself, I have some rules and I follow the rules.听 And yet despite that there鈥檒l be a bit of me anxious about whether they should be having a complete removal of the prostate.听 And so you do live with this uncertainty.听 And the reason I鈥檓 uncertain is because we don鈥檛 know and we鈥檙e running a trial and we鈥檙e taking these patients where we don鈥檛 know which is best for them and we鈥檙e offering them the chance of randomisation.听 And I think this is the best way to answer this question and I really encourage all the patients to consider this.听 But let鈥檚 say we鈥檝e treated someone with HIFU and we鈥檙e monitoring them, they will require long term follow up, which may involve repeated imaging and biopsy and they may require repeated treatment if they鈥檙e unfortunate enough to have a recurrence.听 We know from the data about one in five will need a retreatment and about one in 10 will need their prostate removing and patients have been told that beforehand, they鈥檝e signed up to that but for the majority of patients they will have one treatment episode which gets rid of their disease, leaves them with few side effects.听 A substantial number of patients will avoid major surgery who will have otherwise had it or radical radiotherapy and I think for those men who do avoid it successfully, which is the vast majority, this is a really important thing for them.

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Porter

Tim Dudderidge talking to me in Southampton.听

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Mark Emberton, you鈥檙e also working on a new localised approach to treating tumours in the prostate and one that鈥檚 been in the headlines recently.

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Emberton

Yeah so you鈥檙e describing focal treatment.听 It鈥檚 interesting prostate鈥檚 probably the last organ that exists where we typically treat at the whole gland level.听 When I was training as a urologist I was taught to remove the whole kidney if somebody had renal cancer, today we go to huge efforts to try and preserve as much kidney as possible.听 And obviously mammography has changed the way we manage breast cancer, that happened 40, 50 years ago.听 MRI is now identifying disease, we can see very, very tiny cancers that measure 0.2 ccs, that鈥檚 about eight millimetres across and it鈥檚 not beyond the wit of man then to direct energy at those cancers plus a little margin around them and by doing so treat the cancer and try and preserve function.

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Porter

Now Southampton are using HIFU as we鈥檝e just heard, what are you using?

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Emberton

We鈥檙e using a range of treatments at present.听 The interest a couple of weeks ago related to vascular targeted phototherapy.听 This is a slightly complicated treatment in that we give a drug that sensitises the body to light and then we introduce light fibres into the prostate and that interaction between the light and the photosensitiser releases what we call free radicals which damage the cancer cells and actually stop the blood supply to those cells.

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Porter

And this combination of photosensitising and laser light has been used elsewhere.

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Emberton

It has been used actually, particularly successfully in difficult to treat areas, such as head and neck cancers where there are lots of key vital structures where typically surgery and radiotherapy result in damage 鈥� loss of voice, loss of being able to swallow.听 Photodynamic therapy or VTP is fascinating and offers a great opportunity to patients because it represents a new class of therapy, in other words a new way of treating prostate cancer.听 This is the first mature trial of photodynamic therapy that shows benefit over and above a control, which in this case was active surveillance.

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Porter

Now HIFU鈥檚 work in progress, your own work presumably is still very much work in progress, how long do you think it will be before we鈥檒l know for sure whether these treatments are safe to use in men?

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Emberton

We know quite a lot about these treatments because HIFU, for instance, has been around for about 10 years now and there鈥檚 quite a lot in the published literature.听 So we know about the safety, we know about the tolerability, so men having tissue preservation are very likely to be the same in functional terms 鈥� and by that I mean erections and incontinence 鈥� than they were before treatment.听 We also know what we call the early oncological outcomes, so in other words the cancer results at one and two years.听 What we don鈥檛 yet know is what the outcome is going to be in 10 years because all new treatments we just have to wait for that long term data.

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Porter

But you see localised treatment as the way forward?

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Emberton

Very much so.听 I think our ability to risk stratify, so in other words to be very, very precise about the true cancer that that man has, puts us in a position now to offer a range of treatments that include surveillance, that include very radical surgery and radiotherapy for the very aggressive disease and then in the middle there鈥檚 an opportunity for men to have their cancer treated but really diminish the side effects that have been typically associated with standard treatments.

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Porter

Professor Mark Emberton.听 And if you want to know more about that technique 鈥� and the HIFU being used in Southampton - then there are links on the Inside Health Page of the Radio 4 website. Where you can also listen to last week鈥檚 special on prostate cancer if you missed it.

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Uncertainty is a day-to-day reality in medicine and behind many apparent U-turns in policy. Something we are keen to investigate in a new mini-series in which Carl Heneghan, Professor of evidence based medicine at the University of Oxford, and our own Margaret McCartney, discuss examples where uncertainty has influenced clinical practice. Today it鈥檚 oxygen and heart attacks 鈥� putting an oxygen mask on someone having a heart attack can only help them. Right?

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Heneghan

Yeah so drummed into you is the ABC 鈥� airway, breathing, circulation 鈥� and that airway, when people are having a heart attack, I was drummed into as a medical student you give them oxygen, lifesaving oxygen.听 Yet in 2013 a Cochrane Review came out and actually they questioned, using randomised trials, and said actually giving oxygen in a heart attack actually increases mortality.听 There was some slight uncertainty about that effect at the time because there wasn鈥檛 quite enough trials, quite enough patients.听 Since then there鈥檚 been a further study in Australia called the AVOID trial that actually they showed similar results that actually oxygen actually increases your risk of having worse outcomes, more increase your risk of mortality and that goes counterintuitive to everything that I learnt as a medical student.

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Porter

Margaret, looking at this, you can understand why we give oxygen in a heart attack, it makes sense for everything we know about the physiology that oxygen would be helpful, but had anybody actually shown that?

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McCartney

Well what鈥檚 so interesting is I think this is a case of doctors treating themselves rather than the patient 鈥� it looks like you鈥檙e doing something, it looks like you鈥檙e responding to the patient being ill and it鈥檚 one of those things that I think you expect to get, you expect to have, when you鈥檙e in hospital.听 But actually when you look at the literature, there was a randomised control trial done in 1976 which showed oxygen use with a heart attack and showed no sign of improvement in the treated group.听 Now there was an increased rate of death in the treated group, so the people that got oxygen seemed to do worse, but that didn鈥檛 reach statistical significance and I think a year later there was an editorial saying we should do something about this here.听 In 1997, a couple of decades later, there was an editorial in the Journal of the Royal Society of Medicine saying we still weren鈥檛 sure about this and we needed much better randomised control trials.听 So there鈥檚 a kind of seam of uncertainty that鈥檚 been there for the last few decades really saying we鈥檙e not sure whether oxygen is doing more good than harm in heart attacks.听 And it鈥檚 a bit of a disaster really, in that it鈥檚 taken 40 odd years to actually produce high enough quality trials to make it more certain.

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Heneghan

Do you think the idea is when you have a heart attack you鈥檝e got these main arteries going down around your heart and one of them鈥檚 blocked.听 So what you鈥檝e got to do is get oxygen in there.听 Which that sort of makes sense.听 The problem is when you look at the data and look at the mechanism of oxygen putting too much oxygen actually reduces the blood flow.听 So the idea is that by putting more oxygen you can be making the situation worse.听 And actually the lack of oxygen often leads to vasodilation, so it gets more blood to where you want it to be.听 So that鈥檚 why you get this opposite effect.听 When you start to think about it it actually becomes more mechanistic that it could do damage and that鈥檚 what the evidence is suggesting.

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Porter

I mean it鈥檚 a classic example of Primum non nocere isn鈥檛 it 鈥� first do no harm 鈥� we assume something鈥檚 going to be okay but actually in this case doing nothing might be better than doing something.

听

Heneghan

Yeah and I think it鈥檚 really interesting when you start to stand back and question all of these practices that we use in fact there are other ones that we鈥檙e looking at right now.听 There鈥檚 a trial called the Paramedic2 trial that鈥檚 asking a question about adrenaline, which again is another study.听 When you have a heart attack, you have a cardiac arrest, your heart stops beating, paramedic runs in there, gives you adrenaline and somebody鈥檚 gone uh oh this could actually worsen your outcomes.听 Interestingly last year I had to defend doing the clinical trial because people said it鈥檚 unethical to do this trial.听 Well actually that鈥檚 totally not the case.

听

McCartney

For me this is a big example of eminence based medicine versus evidence based medicine.听 It鈥檚 quite easy, I think, to see when you鈥檙e in a hospital you鈥檙e breathless, your heart is under strain, let鈥檚 give oxygen, it sounds logical.听 This to me is a clear example of where that is not good enough, it鈥檚 not good enough just have exert opinion, to just do things just because they鈥檝e always been done.听 Actually what you really need is high quality evidence and you have to go for that.听 Carl is absolutely correct.听 The tragedy that we have in medicine is it鈥檚 easier to keep repeating your mistakes rather than saying actually we could be doing harm here, we need to stop, we need to do a randomised control trial and find out if what we think is good is actually bad.听 That requires a lot of bravery, it requires a lot of honesty but it鈥檚 the only way that you get better care for people.

听

Porter

The problem with that Carl of course is that sometimes you have to take a leap of faith, we don鈥檛 have the evidence to back up everything that we do, we can鈥檛 suddenly stop doing all of that while we wait for that evidence.

听

Heneghan

I mean that鈥檚 a really interesting point to say we take a leap of faith.听 I think we took leaps of faith in the past and that鈥檚 led to all sorts of problems.听 But actually at this situation what you鈥檙e saying is actually should you be giving room air and getting room air in there versus should you be giving oxygen.听 And at the moment the evidence is suggesting that鈥檚 harmful.听 Right now the other issue is that many of the guidelines are not catching up with the evidence.听 So they鈥檙e four or five years out of date and they鈥檙e still saying give oxygen, give oxygen and we鈥檙e seeing this change where other guidelines are starting to 鈥� ones up to date are saying hold on, use room air.

听

McCartney

And just to be clear, there seems to be an exception for people who are actually short of oxygen, which is not most people having a heart attack.听 So if you鈥檙e short of oxygen, that is in being hypoxic, the situation may well be different in terms of whether you鈥檒l get a benefit from oxygen or not.

听

Porter

But Carl looking forwards then you anticipate that a lot of our current practices, which are based on theories that we should be doing something because it鈥檚 likely to help, when they鈥檙e actually tested under the hard scrutiny of evidence based medicine might go by the board?

听

Heneghan

Yeah, yeah and there鈥檚 been loads of examples of that.听 And what we鈥檙e at is a sort of a point now we鈥檙e just developing and starting the concept of evidence based medicine, it鈥檚 only 20-30 years as opposed to pathophysiological reasoning, all of these physiology types, they鈥檝e been around for a 100 years.听 And actually we have far too little evidence on many of these crucial questions to reduce the uncertainty and to say what we do.

听

Porter

Carl Heneghan and Margaret McCartney who will be back with more uncertainty throughout this series.

听

Don鈥檛 forget to email us with your thoughts on what needs to give in the NHS - the Chancellor鈥檚 purse strings, our expectations of the service, or both. And with that in mind, next week I will be revealing how budget constraints and postcode lotteries are limiting options for some patients waiting for hand surgery.

听

ENDS

Broadcasts

  • Tue 10 Jan 2017 21:00
  • Wed 11 Jan 2017 15:30

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