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BRITISH BROADCASTING CORPORATION
RADIO SCIENCE UNIT
CASE NOTES Programme no. 7 - Sun and Skin
RADIO 4
TUESDAY 13TH MAY 2008
PRESENTER: MARK PORTER
REPORTER: ANNA LACEY
CONTRIBUTORS: TONY BEWLEY
PRODUCER: ERIKA WRIGHT
NOT CHECKED AS BROADCAST
PORTER
The last couple of weeks have been the warmest start to May since records began and we have lapped it up - BBQ's, paddling pools, trips to the beach, and eating and drinking alfresco, all making a welcome change from sheltering from the weather in front of the TV.
But there is a downside to enjoying the sun. Spend too much time in it and you risk damaging your complexion and contracting skin cancer - the most dangerous form of which is malignant melanoma. The cancerous mole.
CLIP
I was just simply lying in the bath one night actually and I asked him to pass a glass of wine and as he leant over me in the bath I noticed on his collar bone a mole, which I had noticed being so dark before. And I just said oh I think that mole has changed colour. He went to the mirror, checked it, said oh I think you may be right. Must have twigged that something was wrong because he didn't go to the doctor willingly but did make an appointment the following week and had it checked out. The doctor clearly recognised it as very sinister straightaway and got him straight on to a dermatologist to have it removed.
PORTER
We will find out what happened to Catherine's husband a little bit later on. And I'll be visiting one of the growing number of high street clinics that offer mole checks to screen for the early tale-tale signs of cancerous change.
And there is new guidance on sunscreens - so what should we be wearing, and when?
But it's not all bad news for sun worshippers. There is growing evidence that sensible exposure to sunlight could be beneficial to health. I'll be finding out how most of the British population have lower than ideal levels of the sunshine vitamin - vitamin D - a deficiency that could lead to a range of illnesses including diabetes and bowel cancer.
But first the dangers. My guest today is Dr Tony Bewley, he's a consultant dermatologist at Whipps Cross University Hospital and Barts and London NHS Trust.
Tony, skin cancer's growing a problem in the UK.
BEWLEY
Absolutely, so we know that malignant melanoma, the dangerous form of skin cancer, has increased two fold in the previous 10 years and we now know that teenagers are particularly at risk - there's been a four fold increase in malignant melanoma in teenagers and the UK now has the highest rate of malignant melanoma in teenagers in the whole of Europe.
PORTER
And we attribute that increase to what in principle?
BEWLEY
To sun exposure. But also we worry a little bit these days about sun exposure from sun beds.
PORTER
So when you say sun exposure, what's change - I mean that we're holidaying abroad now, because it's not the climate in the UK that's changed, it's the fact that we're travelling to the sun?
BEWLEY
Well that's right. In the UK we often take our summer holidays, we have an intense exposure to sunlight and that's particularly dangerous because we worry that it's burning that is one of the main causes of malignant melanoma.
PORTER
So it's going from being pale to that so-called healthy tan look, it's the bit in between that causes the trouble?
BEWLEY
Correct. But also we worry about cumulative sun dose, so in other words if you start having lots of sun when you're a young person, as a teenager, and carry on having lots of sun throughout your life the cumulative - the additional - amount of sun that you have throughout all of those years is a big worry.
PORTER
Well melanoma may be the most serious form of skin cancer but caught early it's also one of the easiest of all cancers to treat isn't it.
BEWLEY
What we know about melanoma is that about 50% of melanomas occur in normal skin, in other words the skin between your moles, and about 50% of melanomas occur in moles that look funny. Now the good news is that if you watch your moles and you're vigilant about the changes in your moles and you catch the changes early enough that treatment - in other words cutting out the funny looking skin mole that you have - is usually curative and that's great and that's the case for the vast majority of patients who come along with a funny looking mole. What we know about melanoma is that when a melanocyte, that's the pigment producing cell within your skin, turns cancerous it will spread horizontally along your skin, so spread outwards, before it starts to spread inwards. Now we want to catch the moles when they're changing, when the cancer spreads outwards rather than inwards. The point is though that we don't have long because once it starts to spread inwards, in other words bigger than one millimetre which isn't very thick in depth, then that's when the chances of it spreading inside the body get much, much worse.
PORTER
And as it does spread it becomes one of the hardest cancers to treat.
BEWLEY
Well that's right, I mean the first place that a malignant melanoma will spread to is the local glands, the local lymph nodes, and a lot of the time the local lymph nodes will mop up those cancer cells and may even just hold them there. Sometimes those skin cancer cells, those melanoma cells, will spread elsewhere in the body and that's when it's particularly dangerous.
PORTER
Well your GP should be your first port of call if you are worried about your moles -but another increasingly popular option is to book in for a check at one of the burgeoning number of private clinics specialising in screening for skin cancers. Charges vary depending on what you have done, but start at around 拢45 for a single mole check, rising to 拢100 or more for a top to toe examination. There are a number of companies who provide the service - including at least one well known high street chemist. I went along to the central London branch of the Mole Clinic to sit in on a consultation with skin cancer screening nurse Megan Ramsay.
RAMSAY
We do both complete checks, from top to toe, where we look at old moles on people's bodies. But we also do a single mole check, which is if there is just one that they're worried then we can image it and send it off to the dermatologist. We take a history first and get any family history or any significant sunburn history from the patient. And then we get them to undress down to their underwear for a complete check where we check them from top to toe - all visible lesions that they're worried about and all the ones that we can see, we have a close look at them. And we apply our guidelines that we follow, which is the same guidelines that the doctors use in the NHS. Any that break those rules then we either need to refer via our own dermatologist by remote dermoscopy imaging, which is taking photos of the moles, or we can refer them back to their GP to be referred to see a specialist.
PORTER
Well one of your patients has volunteered to show us her moles and she's got two quite prominent lesions on her back. Tell me what you think by looking.
RAMSAY
This here is just one of her genetic moles that she's got from her parents and she's probably had it for as long as she can remember. It's one of the fleshier types of moles, not so at risk from melanoma.
PORTER
But it looks quite big so that's the sort of mole that people worry about.
RAMSAY
It does and this is a - yeah this is one of the moles that is very common that people come in worrying about. But it is actually the flat brown moles that people need to be watching because they've got that pigment to them they've got that potential to change. Because of the type of mole that this is, it's a fleshier type of mole with a few hairs coming out of it, not such a problem but it still does have some pigment to it so you still need to keep an eye on it but it is a low risk mole.
PORTER
Okay and further up on her bed we've got something slightly different.
RAMSAY
Yes slightly different, this actually isn't a mole, this is a lesion that's called seborrhoeic keratosis and it's a build up of protein in the skin called keratin, the same stuff our nails and our hair is made out of. They're harmless, they can't get skin cancer. But they freak everybody out because they do everything that we tell you to look out for - they change shape, they change colour, they change size, they get bigger, they fall off, then they grow back. They're often called seborrhoeic warts by GPs but they're not warts, they're not related to the wart virus at all and they're harmless. The way you can identify them is because they usually feel quite dry to the touch and it's almost like they're stuck on the surface of your skin. So it's almost like you could get your fingernail under it and flick it off.
PORTER
Yeah you sometimes hear them referred to as senile keratosis as well because it's something we tend to get as we get older.
RAMSAY
I know I've got a friend in her 20s that has some, so it's not directly related to age. So take comfort in that. So this is harmless so because you're got one you may get more of them, they're very common around women's bra lines - where the bras rub - but very common on the torso.
PORTER
So say we had a flat mole here, what would you be looking for?
RAMSAY
We do have a few little of the flat brown moles, they often are just thought as big freckles but we're looking for any irregularities to the colour, the shape or the size to these lesions. And you can see that these have a nice round shape and a nice even colour, nothing's a perfect circle in nature but as long as they're symmetrical then it's a good general rule to follow. We're also looking for what we call the ugly duckling, okay, so the mole that doesn't belong to the family of moles on your body. It's a good cheats way to check your skin because usually when you can see one mole there's another one quite close to it that looks very similar to it, so you do get a good idea of what is normal for you so that you can spot that abnormal one if it does pop up.
PORTER
So asymmetry, an irregular border, the differences in pigmentation - what about degree of pigmentation, a lot of people think that - ooh it's a nasty dark looking mole, does that make a difference?
RAMSAY
It does make a difference but if you've got dark features - if you've got dark hair, dark eyes and darker skin - then of course your moles are going to be a similar pigment than to the rest of your skin as well, so it's not necessarily the darker moles, there can be melanomas that are white, red, brown, blue, black - so they go in varying degrees of colours.
PORTER
What about size?
RAMSAY
Size - some people just have bigger moles, but it is something that does come into our assessment that we use - anything that's bigger than 7 millimetres fails our guidelines.
PORTER
Because the old trick is that you cover it with a pencil - that's more reassuring than if you can't cover it with a pencil because they're about six mil aren't they?
RAMSAY
I've seen melanomas smaller than the end of a pencil, so it's not the hard and fast rule.
PORTER
There are no hard and fast rules in medicine are there.
RAMSAY
No there's definitely not. So if there's irregular colours and an irregular shape and it just happens to be small why not deal with it when it is small?
PORTER
Megan Ramsay from the Mole Clinic.
You are listening to Case Notes. I am Dr Mark Porter and I am discussing the pros and cons of exposing your skin to the sun with my guest dermatologist Tony Bewley.
Tony, any symptoms missed there? When you look at a mole what goes through your mind, your aide memoir?
BEWLEY
Well when I sit down with a patient who has a mole or a skin lesion that they're worried about I'll follow those kind of rules. I'll make sure that we look at the patient all over, so I will want to look at pretty much all of their skin, including the scalp, underneath the feet - on the soles of the feet - in between the toes and so on. And then I'll be looking at particular skin lesions and I'll want to look particularly at what's called the ABCDE rule. And as we've heard the A stands for asymmetry - anything that looks or has a funny border, anything that has a funny shape, is more worrying. The B stands for border - if you have pigment in the centre of a mole, so the mole is darker in the middle and lighter at the edge, that's much less worrying, whereas if it's darker at the edge and the darkness at the edge is growing out of the edge that's more worrying. Also if you have lots of different colours within a mole, so if there's several shades of brown and black, that's more worrying and that's the C part of that term. And then the D stands for diameter - anything that is bigger than six millimetres is slightly more worrying but many people have moles that are bigger than six millimetres which are completely normal, so don't be too worried about that, but if a mole grows then that's more concerning. And then E, and most importantly E stands for if you're in doubt go and see an expert. So if you're not sure go and see your GP or go and see a dermatologist and then check it out and make sure that your worries are either unfounded or if it is going to be something that's a bit more dangerous that it's seen and treated straightaway.
PORTER
Which brings me back to the Catherine Marsh story. We heard from Catherine earlier, describing how she'd noticed an unusual mole on her husband's neck when he brought her a glass of wine in the bath. He was 40.
MARSH
The holiday which caused the problem was in August, we noticed in February, he had the mole removed in March and he died 14 months later. The heartbreaking thing is that I have a photograph of him five months before I noticed the mole and in this picture we were on holiday in Southern Spain and he's sitting in the deckchair, sun beating down, with a perfectly healthy looking mole and within five months obviously it had gone this very dark chocolate colour and in the space of that five months it had progressed too far to save him. And had we noticed early enough the cancer hadn't spread into one his lymph nodes his chances of survival would be 95%. Because it had progressed into one of his lymph nodes his chances of survival plummeted to 28%. What I understand goes on in Australia, for example, is if you stop at a motorway service station and you go to the ladies loo is on the back of the door, rather than having insurance posters as we have, you have pictures of melanomas and the danger signs.
I would really encourage people to check their skin as carefully as they check for all the other better known cancers and as soon as they notice anything different to go to the doctor.
PORTER
Catherine Marsh.
Tony, what proportion of patients present with melanoma when it's a stage that's easy enough for you to remove as an outpatient - a simple incision - hoping for a cure?
BEWLEY
Well the first thing to say is what a tragic story that we heard just a moment ago, just five months and that change was so advanced. I think I would like to point out that melanomas can be very slow to progress and can be very non-aggressive and sometimes they can be very aggressive, as we've just heard. The good news is that the vast majority of patients who come to our clinics are in the very early stages and that means that they have a superficial melanoma, which means it's a very thin melanoma. And the overwhelming majority of those are cured completely just by having the mole cut out, or the melanoma cut out, with a one centimetre margin - which sounds a lot but actually isn't that much. And it's life saving.
PORTER
Well the aim is to catch them early but Phillip Windyatt's melanoma wasn't picked up earlier enough, it had already spread to the lymph glands under his left arm when it was diagnosed eight years ago, and he has been battling ever since.
WINDYATT
It was a mole that had always been brown but it was uneven, it wasn't round, it wasn't symmetrical, it was asymmetrical. So it was - always potentially a mole that you needed to keep an eye on. And it went a very dark blue, almost the colour of wine, and it bled as well, that's when I went to the doctor and went through my GP to St Thomas' in Central London. And then I went on the melanoma road which is lots and lots of surgery. You know I had the melanoma removed but unfortunately it had spread under my left arm into the lymph nodes, so all the lymph nodes were removed. That seemed to be the end of it, so I had a really weird situation where I was discharged from treatment, I thought okay well get on with my life, level two, stage two, melanoma the odds are pretty good. So I thought okay you know I got a let off. But in fact a couple of months later we had a tumour in my neck as well, it had spread into my neck and that was getting really serious and I thought - and again you know that was a five hour operation I had. And that was removed. I was okay for a couple of years but it did come back again to the original site a couple of years later - 2002. Two more operations and I had those cut out as well.
PORTER
Phillip Windyatt - whose story highlights why doctors are so keen on prevention. It can be a very difficult cancer to cure.
Tony, most people are now hopefully aware of the need to wear sunscreens when they're on holiday - or indeed if they're about in the UK doing an activity outside. But what about day-to-day activities, I mean just going out, should we be wearing sunscreens routinely?
BEWLEY
Well there's a lot of confusion about sunscreens. Basically sunscreens come in two varieties - there are the absorbent sunscreens which don't make you look white and don't give you that kind of ghostly look and there are reflectant ones that makes you look ghostly and a bit ghastly really. Those are the best ones unfortunately, it's always this way isn't it. But the ones that make you look a bit white and a bit ghostly are actually pretty good and the reason for that is that they're smashed up particles of some chemical called titanium dioxide which reflects the sunlight away and that's much, much better. What we tend to advise patients to do is to follow the Sun Smart campaign, there's an organisation called the Cancer Research UK and they have come up with an advice which basically is around the acronym smart. And the S stands for spend more time in the shade between 11.00 and 3.00. The M stands for make sure you never burn. A is aim to cover up with a T-shirt, hat and sunglasses. R is remember to take extra care with children and that's very important. And the T is then use a factor 15 sunscreen.
PORTER
Okay but briefly, what should we be wearing - a factor 15 you mentioned there - I mean there have been some recommendations I've seen recently that we should be using a minimum of 20, indeed should be using 30, 40 or even 50 in younger children, what would you use on your family?
BEWLEY
Well I think it depends on your skin type. So if you're Irish or Celtic skin with red hair and blue eyes then you should be using a factor 50 because you will burn very quickly in exposure to sun, so factor 50 is quite important. Whereas if you're a darker skin then you can go down a bit. But I personally probably, if I'm sitting in the sun, wouldn't go any less than factor 25 and I've got reasonably brown skin.
PORTER
And your children?
BEWLEY
And again with my children I'd definitely go for factor 50. I think the story about children and their increased risk, especially as time goes on, more recently the evidence is that children are definitely more at risk and we need to protect them much more than we have been doing.
PORTER
Okay Tony, but some exposure to sunlight is regarded as essential by some people because it's the only way that many people can get enough vitamin D. Lack of that vitamin is normally associated with weakened bones and rickets, but milder degrees have recently been linked to a number of other serious problems, ranging from diabetes to bowel cancer. Our changeable climate means deficiency is a surprisingly widespread problem, that is set to get worse as more and more of us cover up and apply high factor sunscreens. Could the pendulum be swinging too far the other way? Anna Lacey went to see David Bender, he's senior lecturer in Biochemistry at University College London.
BENDER
If you go back to the 1920s they say that in Central London at the Royal London Hospital the most common paediatric operation was breaking the legs of children with rickets to splint them straight, so they knew the clinical deficiency disease and during the 1920s people tried to find out what it was in the foods that were known to cure the disease and also work out this relationship with sunshine. So the enormous advance was discovering vitamin D and how to make it synthetically to add it to infant food.
LACEY
And did that make much of a difference?
BENDER
That made an enormous difference. I mean I'm from the generation born at the end of the war where rickets was totally irradiated. And then unfortunately what happened was a small number of children were sensitive to vitamin D and they developed signs of vitamin D poisoning. So the amount added to infant foods was reduced so that no child was at risk of poisoning. But every time anyone's gone out and done a survey they've found about 10% of toddlers in the inner city areas where there's relatively poor sunlight exposure, about 10% of them have sub-clinical signs of deficiency.
LACEY
But the threat of deficiency isn't just for children. Large numbers of adults in the UK are either deficient in vitamin D or have levels below that needed to be healthy. Elina Hypponen at the Institute of Child Health has tried to work out the scale of the problem.
HYPPONEN
If you think about the most severe form of vitamin D deficiency it's a question about millions. But if we think about the concentration that would be related to achieving optimal health then the problem is even more severe and in the UK, according to our own study, there was 90% of the white skinned, Caucasian population, had concentrations that were lower than those believed to be related to optimal health.
LACEY
So can people tell if they're deficient in vitamin D because if so many millions of people are affected then surely there must be some signs?
HYPPONEN
When it's the most severe form and that's prolonged over time then the severe form is more typically manifested as generalised pain and this can also be misdiagnosed to all sorts of conditions. So it's not very clear cut. But when one is starting to talk about concentrations that would be associated with the best health there is really no way to tell. There is nothing really characteristic for vitamin D deficiency as such.
LACEY
One of the easiest ways to top up on vitamin D is to go outside on a sunny day. But the problem in the UK is that for a few months of the year we have the wrong kind of sunshine.
BENDER
The cut off is roughly about Watford and north of about Watford in winter time there's nowhere near enough sunlight of the right wavelength. And if you go further north up to Scotland then in the north of Scotland, even in summer, there may not be enough of the right wavelength.
LACEY
Now I must ask why Watford, indeed, why is that the cut off point?
BENDER
Watford is sort of a guess really but it's about 45 degrees north, the sun then is coming in at such a shallow angle that all the ultraviolet of the right wavelength is being blocked.
LACEY
Now another way of being able to take vitamin D is through a supplement form, so taking a tablet, what kind of levels should people be aiming for - how many tablets, what is enough to not be deficient?
BENDER
We're probably talking about 10 or 15 micrograms a day and really what we're saying is that is enough to keep the blood level of a housebound elderly who don't get out in the sunshine at the same level as you see in younger people at the end of winter.
LACEY
So that's after they've not been able to produce any vitamin D?
BENDER
Yes that's after they've not been producing very much. So that, if you like, is very much a bottom level and there's evidence building up that all sorts of conditions, including various cancers, diabetes, obesity, high levels of intake are almost certainly desirable.
HYPPONEN
Infants who received vitamin D supplementation regularly during their first year of life and in relatively high doses, they had an 80% reduction in their risk of Type 1 diabetes later in life. Type 1 diabetes is an autoimmune condition where the body's own immune cells are starting to destroy the insulin secreting beta cells in the pancreas and it is believed that the vitamin D intake, especially early in childhood, can affect the pattern of immuno regulation later in life in such a manner that this autoimmune process is less likely to occur.
LACEY
Recent studies suggest that vitamin D can also reduce the risk of bowel cancer, although it has the potential to protect on a much wider scale.
HYPPONEN
When they were looking at geographical distributions between different cancers they found that as expected the risk of melanoma was more common in more sunny areas and got less common in more northern locations. But for every other cancer that they were looking at the total opposition was true. So that proposed that something in the sunlight might be actually protecting from many other cancers although it does increase the risk of malignant melanoma.
LACEY
Now do you think that we'll be able to strike a balance somehow between protecting our skin from melanoma but letting ourselves get enough sunlight so that we can produce vitamin D?
HYPPONEN
Yes. I think that there is not such a big conflict between these two things because the melanoma risk the important thing is to avoid sunburn and for vitamin D production there is never any need to expose skin, even close to the risk of burning. We're talking about much more moderate and shorter term exposures to the skin.
BENDER
I think we probably are now saying either supplements or let's all go off and have summer holidays somewhere nice and sunny. But vitamin D it really is beginning to look as though levels of intake greater than we thought would have to come from supplements, we think, and the evidence is not yet as firm as we'd like, is going to be protective against these various conditions.
PORTER
David Bender talking to Anna Lacey.
Tony, I saw you nodding your head there, you're not in total agreement with us spending too much time on summer holidays.
BEWLEY
Well summer holidays are fantastic and I love my summer holidays but the important thing is that you don't need to expose yourself to huge amounts of sun either to get the vitamin D or to have a good holiday. So it's still important to protect yourself.
PORTER
Well put that into some perspective, when we're not talking about huge amounts of sun what do you mean, how much time do I need to spend in the sun without sunscreen on for me to make enough vitamin D to be healthy?
BEWLEY
Well the first thing to say is that the link between vitamin D and some of these conditions is putative, in other words it's theoretical, it's not proven. However, there is definitely a condition - rickets and so on - where you have low vitamin D levels which can be very dangerous. I think the Cancer Research UK's comments about this and my own organisation - the British Association of Dermatologists - is very clear. You can get a lot of the vitamin D that you need from just ordinary food, healthy food, like oily fish - sardines, mackerel, salmon and so on - and also if you need to have a bit of sun exposure 15 minutes in the early part of the day or the early evening, so not at the height of the day, so just to walk to the school or putting out the washing on the line is enough to give you enough vitamin D to run your life.
PORTER
So good skin protection and getting enough vitamin D need not be mutually exclusive, it's not one nor t'other?
BEWLEY
Absolutely, they can both be included.
PORTER
We must leave it there - Dr Tony Bewley, thank you very much.
Next week's programme is all about the prostate. I'll be watching a robot designed to make operating on the gland easier, and finding out why the death rate from cancer of the prostate is so much lower in the States. What are they doing that we aren't?
ENDS
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