Exploring Dermatology with A/Prof Alvin Chong from Spot Diagnosis podcast: From Skin Cancer to Sun Protection

Did you realise that 16 percent of what general practitioners see each day relates to the skin conditions or dermatology? And that 85 percent of Australians will suffer from acne at one stage in their life? 70% of Australians by the age of 70 will have developed a skin cancer and one in 17 patients would've developed by the age of 85. A melanoma it's my pleasure to interview associate professor Alvin Chong, a dermatologist from Melbourne who also runs his own podcast series called Spot Diagnosis. I'm going to speak to him about common dermatological conditions. G'day and welcome to Aussie Med Ed, the Australian medical education podcast, designed with a pragmatic approach to medical conditions by interviewing specialists in the medical field. I'm Gavin Nimon an orthopaedic surgeon, and I'm based in Adelaide, and I'm broadcasting from Kaurna land I'd like to remind you that if you enjoy this podcast, please subscribe

It is my pleasure now to introduce Associate Professor Alvin Chong, a specialist dermatologist in Melbourne, in Victoria. He has an appointment as a VMO at St Vincent's Hospital in Melbourne and at the Skin Health Institute. He is also an Adjunct Associate Professor at the University of Melbourne. Alvin is the creator and co host of Spot Diagnosis Podcast. Welcome Alvin. Thank you very much for joining us on Aussie Med Ed.

It's a pleasure to be here, Gavin. So it's nice to be on somebody else's podcast for once.

Yes, exactly. Being a co producer of another podcast, it's great to have you combining together to actually introduce different topics. I started Aussie Med Ed three years ago as a way of introducing medical topics to medical students and to also GPs. I believe you undertook the same sort of philosophy, but with the idea of having predominantly a dermatology focus. Can you tell us a little bit about spot

diagnosis, please? Yeah, sure. So spot diagnosis podcast. We actually started recording it in 2019 and the reason why we recorded it and we started this podcast series was due primarily to the lack of, um, education on skin diseases. That's almost endemic in medical schools. I said, I'm an academic at university of Melbourne and we, for a long time, all we had to teach in dermatology with three one hour call lectures in four years of medical school. Of something that is 16 percent of the work of a GP. That is clearly inadequate. And we decided, okay, why don't we create our own podcast series at the Skin Health Institute. And the aim is really to introduce more dermatology topics to these poor medical students. Because you can imagine if you go to med school and you come out after three lectures given in second year, you're going to have virtually no working knowledge on skin. And that's basically a lot of what we see. But as it stands, we recorded the whole season 2019. And we launched it in March, 2020, which as all of us know, that's when the pandemic was declared. It was just timing. We thought we got to launch it and we did, but it was quite interesting because the entire world of medical education pivoted towards online education. And suddenly we had a lot of listeners and now we're on a fourth season. The reason why we have a podcast like this is every month we talk about a different topic in skin disease, for example. eczema or psoriasis and we invite a local specialist dermatologist with a particular interest and we will present very good quality evidence based information in a format that is accessible to all health professionals. So it's not only to medical students but also to GP trainees, GPs and nurses. And we're in our fourth season, we've had 42 episodes and it's going very well. We've just cracked 50, 000 downloads. Which for a niche, uh, uh, podcast and demonstrator is not too bad. It's excellent.

It's fantastic news. And I've actually listened to the fair few episodes and I'm really enjoying it. It really expands upon the area we're working on and trying to provide a general area. You're going down a specific pathway. And it is really important because when I went through medical school, I figured that a lot of skin conditions could only be treated in one or two ways. I believe it's actually progressed a lot over the years, and we'll go into that in a little while. What are the more common types of conditions that you would see or the things that are important to mention today?

So, I guess. We're very bound by geography and so if you're working in the tropics, for example, you'll be seeing a lot more tropical skin infections. Australia is fairly unique. We have, uh, unfortunately, the dubious distinction of having the highest skin cancer rates in the world. And it's partly because we're a country that's bathed in high UV with a largely susceptible Caucasian population. In Victoria, most, but probably about 40 to 50 percent of the work that I do is related to skin cancer. So diagnosing skin cancers, whether they're keratinocyte cancers or melanomas. And then the other 50, 50 to 60 percent is related to inflammatory skin diseases, eczema and psoriasis. We see acne a lot, and then there are all kinds of disorders which involve skin and integument like hair diseases. And after you deal with the common things, which make up 80%, then the other 20 percent can be almost anything, for example, planus, lupus, so the full spectrum of weird and wonderful things in, as well as common things.

And of the skin cancers, you say, what are the ones that we need to really worry about? Yeah,

sure, sure. Traditionally, we divide skin cancers into non melanoma skin cancers. And it's got a new name now is keratinocyte cancers. And there are things like basal cell cancer, which is by far the most common type of skin cancer that you're going to get out there, followed by squamous cell cancer. So these are the two main keratinocyte cancers. And then you have melanoma. Melanoma stands separately by itself. The good thing about keratinocyte cancers are, even though they're common, they don't result in a lot of death. Okay. So basal cell carcinomas, for example, will occur. In about 70 percent of the population once they reach the age, uh, 70, so it's really common. They occur in, uh, sun exposed parts of the skin, like the head and neck. They're kind of pearly, growing, ulcerated, um, nodule on the nose or the ears or the, or the forehead, usually asymptomatic. The good news is they don't metastasize. Once they're diagnosed and, and excised, then they're cured. squamous cell cancers are, um, the next one along. They They occur probably about a third as commonly as basal cell cancers. The ones that are on the head and neck can be nasty, so if they're on high risk sites like the scalp, the nose, the ears, the lip, they can metastasize. So head and neck squamous cell cancers are a little bit more concerning, but usually they are low risk sites like on the forearms, on the back of hands, and they're not that dangerous. Melanoma is, uh, a completely different beast. Fortunately, they're not quite as common as caries from the side cancers, but they're still common enough. So they're going to be about 17, 000 diagnoses of melanoma per year. And they're going to affect about 1 in 17 Australians by the time they reach 85. And the death rate from melanoma is still reasonably high. So I think the latest, uh, data shows that about 1, 200 to 1, 400 people die of melanoma per year. So that's. As many as in car accidents. Okay, this is considered the third most common cancer after prostate and breast. And it's still a killer. The good news is that you can actually diagnose it early. And it's largely preventable using sun protection.

And I believe there's been some new developments in the diagnosis over the last 20 years or so with dermoscopy and other techniques. Perhaps you can outline a bit about that,

please. Yeah, melanomas used to be, certainly when I was in medical school, we learned about the A, B, C, D, E, right? A for asymmetry, B for border irregularity, C for color variation, D for diameter, and E for elevation or evolution. And that's still very useful because it's like the, if you don't have a dermatoscope and you're looking at a dark lesion, a pigmented lesion, you use all those criteria to inform you as to whether something is worrying or not. Of the A, B, C, D, E, it's the E, evolution is the main concern. If it's something that's changing, it's a concern. But over the last 20 years, the use of the moscopy, so the microscope is really, it's like a glorified microscope, times 10 magnification, uses LED light, and you place it on the skin with a liquid medium to reduce refraction. And that allows you to look at lesions a lot more closely and also can peer through the top layer of the epidermis into superficial dermis. So you can have an appreciation of color and structure. And there's a way to learn the moscopy and that in itself has resulted in earlier diagnosis of melanoma and also better differentiation. So you're not cutting out pigmented separate keratosis, which are harmless, but we can differentiate them from suspicious pigmented lesions. So it really improves the benign malignant ratio. And I think the moscopy training is now done by a lot of GPs. Uh, certainly it's a very important part of being a dermatologist. But it's still not very well taught outside general practice and dermatology, for example, in medical schools. Certainly in Melbourne, it's not taught

there. Do you think this would also be supplemented by artificial intelligence and the use of computers to help diagnose it as well?

The first thing is, I think there needs to be more teaching in Demoscopy. Per se, across the board, because it's like listening to a stethoscope. All medical students learn how to use a stethoscope to listen to heart sounds. I think medical students should learn how to use a stethoscope because But it's not so easy to teach, you need expert demoscopists to teach. And I think it depends on the medical school if the resources are limited. And they say, Oh, you can only have a very limited amount of time learning dermatology. Then they try to teach everything rather than just go into great detail in one topic. So it's not so easy. Now artificial intelligence is very different. Anything that is visual and that can be analyzed, uh, pattern analysis. Okay. Anything that's that uses pattern analysis, artificial intelligence can do faster and more accurately than we can. Okay. That's actually been proven. There are now studies to show that an AI program can diagnose a melanoma. As accurately as a practicing expert dermatologist and much faster. Okay. So, so we are heading down the path of hopefully using AI as an adjunct to the way we diagnose things. The kind of naysayers would say that we're heading on a path of extinction. It's going to take over. I don't think that's going to happen. I think the, fortunately there are legal structures and medicine is a very conservative way of organizing thought. And so we're still largely protected by legal structures, by responsibility. You can't really hold AI responsible. If it makes a mistake, you can hold a doctor responsible. We make a mistake. But there's a lot of research now where they use AI to look at pigmented lesions. Yeah, I reckon

the AI is interesting because I think it's going to be an extra tool to supplement your clinical acumen. One question though that comes to mind when you're talking about the stethoscope and also other cardiology devices is that over the years, the stethoscopes now become noise cancelling electronics. The other cardiology things like blood pressure machines you buy at the chemist shop to do your own home monitoring. Do you think it will come a day where you can buy your own dermatoscope with an AI? So at least you can monitor it and then. When you're worried, go to the dermatologist, get advice from there.

Yeah, so, yeah, good question, isn't it? There are now AI linked apps, okay, and they're not widely used. I have seen apps where you can take a picture of a pigmented lesion and send it to an AI space, and then it's diagnosed, and then, uh, the recommendation, this is worrying, you need to see a dermatologist. This is benign, you can leave it alone. Okay, with all the disclaimers, whether we like it or not, it's actually being used already. It's being used right now. And they're pretty good, they're pretty good. I had a patient who, who came in and the app had picked one lesion which they were worried about and two lesions that they said were harmless. So I said, let me have a look at all of them and it was accurate. The lesions that they said were harmless was actually quite sophisticated. You need a bit of knowledge to actually say that it's harmless. And the one that they said was a malignant was clearly malignant. So they're really intelligent. Obviously at this

stage, so anyone listening is to recommend you to see a dermatologist rather

than this. Correct. Correct. What was interesting was this person had used an app and the recommendation was go and see a dermatologist and get it treated or go and see a doctor to get it treated. So that's probably the way triaging things. I think AI can be used to triage things. Excellent. I believe

there's been some further advances, not only in the diagnosis, but in the treatment of these skin cancers, particularly melanoma. Yeah.

So the main advance is actually in the treatment of melanoma. So it wasn't that long ago when, if you get diagnosed as having metastatic melanoma, it's over. Like chemotherapy doesn't work. The median survival is something like six months, so it is just a lethal disease. But everything changed with a type of treatment called checkpoint inhibitors. Okay, so checkpoint inhibitors are incredible drugs that actually allow the body's immune system to recognize the melanoma and to kill it. Okay. There is one called Pembrolizumab, which has been used now at least over the last 10 years and it is life changing. It can actually produce. Complete metabolic response in patients with widespread melanoma. And it is almost like science fiction. A magic bullet. Like a magic bullet. You got a f l in, in, in Adelaide, of course, by afl, right? It's a highly of afl. Oh, okay. All right. Let's, we can argue about that. And Victoria, the team Hawthorne had a, a really, a well-known play and he had, this is really clearly documented in the public sphere. He had a melanoma on his lip. Okay. And that was excised. And then he developed a metastatic melanoma in his lungs. So now, usually you get a diagnosis of metastatic melanoma in your lung. It is game over. He was actually given checkpoint inhibitors and they produced a complete metabolic response so well that he could actually go back and play for Hawthorn and captain Hawthorn. This is literally the science stuff of science fiction. So. Not everyone who gets treated with checkpoint inhibitors will respond that well, but you have great hope and previously there was none. Okay, so these checkpoint inhibitors are now being used in all kinds of cancers, but melanoma is one where it has created a huge inroad. Excellent.

So has it improved the prognosis significantly across the board? So it's mainly a

metastatic melanoma.

Okay. Brilliant. So, of course, the first diagnosis when you start off with a melanoma is initial excision. What's the role of the punch biopsies versus excisional

biopsies? Okay, so that's a very good point, right? So, we actually recommend that if someone has a pigmented lesion that is suspicious for a melanoma, that the initial biopsy be an excisional biopsy if at all possible, rather than a punch biopsy. And the reason for that is, um, false negatives. So a melanoma is not uniformly malignant. Okay. So you have a pigmented lesion and some of it may actually be benign, whilst other parts of it may actually show the invasion. And if you actually punch biopsy the wrong bit and you get a diagnosis, say, oh, this is just a benign nevus, it's a disastrous false negative, and it can lead to delays in treatments. And this has happened. Pigmented lesion, punch biopsy, it was called benign on the punch. But it actually because missed the malignant bit and the patient presents like a year later with metastatic melanoma. So excisional biopsy for suspicious pigmented lesions, if at all possible.

So there's not a concern that it might spread the melanoma by doing a punch?

No. So you don't spread melanomas by punch. It's been untruly proven. That doesn't happen. It's a misdiagnosis.

Okay. Excellent. And the other cancers themselves, they're fairly straightforward. So

if we talk about basal cell cancers, the majority of basal cell cancers are treated by excisions with clear margins. Superficial basal cell carcinomas can be treated reasonably well. with a medication called Imiqumod. This is a topical treatment. You apply it for a six week period. It causes quite a lot of inflammation. And, uh, essentially, Imiquumod stimulates the body's immune system to kill the basal cells and to clear them. So, the clearance rate is about 80%. It's pretty good, okay? Particularly in, in areas where surgery is considered difficult. For example, the lower limbs. But we use them primarily in low risk lesions in low risk areas. So, on the trunk, on the limbs, imicumot will work quite well. And it has to be superficial basal cell, so not an invasive nodular basal cell carcinomas. And what about

SCCs for cryotherapy, is

that even used? Okay, so if we talk about squamous cell cancers, invasive SCCs, there's only one treatment that I, I would recommend if at all possible, and that's actually surgical excision. Because the risk of metastatic diseases is present. So, if you got an invasive SCC in the head and neck area, it needs surgical excision with a good margin. That's the, the only thing that I would recommend. If you have lower risk SCCs, for example, multiple small SCCs on arms and lower limbs, potentially they can be curated off. You can try cryotherapy, but it's a higher risk situation. They tend to recur. And if they recur, you'd have to excise them. And unfortunately, not a lot else has been described for SCCs there. It's still the night, primarily the night. Obviously,

there's a lot more to skin cancer than just this little bit, but so we'd refer you to Spot Diagnosis for more information. Yeah,

absolutely. Next, we can talk about the other condition,

the other one that you might see commonly is acne. Do you see a lot of that as well? Yeah, I

see a lot of acne. Yeah, absolutely. So, Acne, it's, it's considered the most common skin disease because the epidemiology is like about 80 to 85 percent of young people from 12 to 25 will have some degree of acne. So it's really almost universal. Now again, it's a spectrum, right? So if you take a hundred kids, probably about 80 of the hundred kids will have mild acne, maybe which can be treated reasonably well with over the counter treatments like benzoyl peroxide. In amongst the spectrum, you're going to have the extreme ones, so about 10 percent have increasingly severe acne, nodular cystic acne, with a lot of scarring, and those ones are going to need further treatment apart from over the counter drugs. So the options would include oral antibiotics, topical retinoids, um, if you're female, contraceptive pills and anti androgens. And then the most commonly used. medication that is effective in severe acne is isotretinoin, also known as orotane or roacutane.

So the roacutane obviously has a sort of a stigma about it of having some side effects, but I believe that it's not quite as common these side effects as what people think they are. Yeah, yeah. Look,

it was very interesting when early on when I had a chat with you over the phone, I said, Oh, we use quite a lot of roacutane. I think you said, Oh, isn't that associated with depression and yeah, correct. And this is one of those kind of myths about, uh, raocutane. Um, it, it, the reality is that racutane is actually less likely to cause depression than severe acne. Okay. I think I, I sent you some information about a study where they looked, this is a, a huge study where they looked at a couple of thousand kids in Norway. Yeah. And they found that. These are about 4, 718 to 19 year olds and they looked at kids with substantial acne versus kids with minimal acne. So substantial acne, about 15 percent of those kids had substantial acne. And they found that the risk of suicidal ideation has increased 1. 8 times, mental health problems increased like 2. 25 times, low attachment 1. 5 times. So severe acne itself can cause a lot of mental health issues as well as social issues and isotretinoin or roaccutane is the best treatment for this type of acne and there have been multiple meta analyses done which show that roaccutane does not actually increase the risk of depression per se. In this group of patients you really have a slightly more high risk. Now you can have very rarely someone takes racutane and they develop some mental health issues, but that is actually fairly uncommon. I've only had to stop a handful of patients in 20 years of dermatology practice. Usually, they would use a low dose, we guide them through. If a patient has pre existing depression, we often co manage them with a mental health professional. And once the acne clears, you can see them change, their outlook on life changes, often just blossom. It's quite a remarkable drug. So with

this algorithm of treatments options, the old scarred acne, does that still occur or is it less commonly now?

Yeah, I think it's a lot less common. All of us remember when we were growing up, looking at patients with terrible acne and almost no treatment, and they end up with their face full of scars or back full of scars, I think the good thing nowadays is that. The medical community is a lot, uh, more cognizant of treatments and they're less likely to allow it to get to that stage. And the other thing is also parents, parents now far more likely to seek help early on in a patient's acne journey rather than waiting for the scars to develop. That's brilliant. Sorry.

Certainly there's options available. What other conditions do you treat that's worth

mentioning today? The kind of conditions that I see a lot of, because they are quite common, the kind of inflammatory skin diseases and the way that psoriasis, for example, has been treated over the last 10 years is nothing short of miraculous. We know what psoriasis is, I'll just run it through with you. This is a inflammatory disease, yeah, where you get red plaques, often quite itchy on extensive surfaces. So they cover your arms, your legs, your back. Their scalp, it's always there, it's itchy, it's scaly, it's flaky and it affects 5 percent of the population. So quite a lot of people and, and like in any disease, if it's mild, it's not too bad, but we see quite severe psoriasis where patients are covered with this red rash and it stigmatizes them. They can't go anywhere. They can't wear t shirts. They can't wear shorts. If it's on the scalp, they, they shed dandruff everywhere. And I've got patients who have spent 20 years of their lives, not knowing what their normal skin looks like. Okay. So it is absolutely horrendous, itchy all the time. Every time I take their clothes off, there's a pile of scale, and I know their partners often have to go around with a vacuum cleaner just chasing after them. It is stigmatizing and absolutely debilitating. So, about 15 years ago, the first biologic treatment for psoriasis was found, okay? And this was a TNF alpha inhibitor. So with this new treatment, it's given us an infusion, and within weeks, the patient is completely clear of psoriasis, and it's a miraculous drug. And we're currently in a golden era of these biologic treatments. And so... We now can use these injectable drugs and they not only block TNF alpha, they also block interleukin 17, interleukin 23, and they're all given subcutaneously in different intervals. One of these medications, risincuzumab, is given one injection every three months. And they have been nothing short of astonishing, astonishing. So imagine if you're completely covered with psoriasis. You come and you get given one of these medications and it clears you. And as long as you're on it, like one injection every three months, you remain clear. Okay. So that's the type of response we're getting as close to a cure as you can get. And it is, it's revolutionized the way we treat psoriasis.

Is it because psoriasis is an autoimmune disorder that this is an anti immune reaction or a immune suppressive type effect?

So psoriasis is very polygenic and. And the way psoriasis works is there's two parts to it, okay? There's a lot of inflammation and there's a lot of proliferation of skin. And they have these pathways. So the psoriasis pathway, they found these cytokines, okay? So the interleukins, which are a part of the whole psoriasis cascade. And what the investigators have found is that if you actually block one of these interleukins, for example, interleukin 17 or interleukin 23, You basically just stop the whole process dead, but because it is so specific, you're only blocking a very small part of the immune pathway, the, you don't get the kind of massive immunosuppression like you get with, let's say, methotrexate or cyclosporine. Okay. So it's very targeted immunotherapy and it is incredibly effective. Wow. It's

pretty amazing. It is amazing. So, what about the role of the ultraviolet treatment in

treatment of psoriasis? While I've been raving about these biologic treatments, there is a catch, okay, and there's always a catch. They are really expensive. So, if I put a young man on a medication like risincuzumab, it will cost the government approximately 20, 000 Australian per year for the rest of his life, okay? So, there are certain types of limitations and cost is one of them. We still have to show that the patients have, number one, severe enough psoriasis and they fail conventional treatments. So conventional treatments would include things like ultraviolet light treatment or methotrexate or acetretin or cyclosporine. If we fail two out of the available treatments, then we can then apply for a biologic treatment. So we still use the ultraviolet light treatments. as a form of first and second line treatment. And if someone's psoriasis clears an ultralight treatment, we don't have to put them on lifelong injections. But if they don't, we can.

And for the medical student, the ultraviolet treatment doesn't involve just going out in the sun and sunbaking. It's a little bit more to it than that. Can you perhaps

outline about what that involves? Yeah, sure. Ultraviolet light is basically a component of sunlight. Okay, so you have UVA and UVB and UVC. Okay, so UVC, it's deadly and filtered out by the atmosphere. So we usually have UVB and UVA. In the past, we used to do something called PUVA and PUVA. So the P stands for Psoralen, where you take a tablet called a Psoralen and that actually makes you more sensitive to sunlight and then you stand in a, in a UVA booth and you get a wavelength UVA. To clear the skin. So what the U V A does is actually produces a local immunosuppression of the skin where it's shown, and that's very effective against psoriasis, eczema, things like cutaneous T-cell lymphoma. But it's very tricky because once you take a sorein, it's gonna be in your system for 12 to 24 hours, and everywhere you go, you need to be sun protection, you need to wear sunglasses because you can take a soul and walk under the sun and you get a bad burn. So it's been superseded by something called U V B treatment. UVB is a wavelength where, which can actually cause skin cancer, but it also causes an immune system to calm down. And there is a wavelength which we particularly like, the 319 nanometers, treatment. That is a lot less of a hassle. You go three times a week, we start low and we gradually increase the dosage. And what it does is it helps to clear, dampen the immune system locally. So you clear the cirrhosis. The problem, if you have a lot of UV treatments, and if you have susceptible skin, Caucasian skin that burns easily, you're going to open yourself up potentially to risk of skin cancer. So it's always a bit of a, that's a risk benefit ratio, catch 22, you know. So we still use that, by the way. So the ultraviolet

booths is still the, look the same. There's big, like almost like big changing rooms. Yeah.

Yeah. They look like Star Trek transporters, big kind of round things surrounded by blue light. And it's convenient if you live close to one, but if you're from the rural area, then it's really very impractical for you to go somewhere. Two or three times a week. So not all places. Half of them, certainly dermatologists have them, but our patients have to come and visit our practice two to three times a week to have this treatment, so it can be a bit of a hassle. One question

that just came to mind while we were talking before about melanoma. We're talking about Australia having the largest population or largest incidence of it. Now, one thought I always thought is somewhere in Europe, like in Europe, where a lot of the people are perhaps in the UK to go out and sunbake from the moment the sun comes out, is it not increased the incidence there? And with us being trying to be more UV protection and more slips, hops, slap, is that reduced and has equalized

the beauty? You can unpack that question in two bits. So the first thing is. If you have a population like in the UK, where they seek the sun. I know this because I've, I've, uh, worked there, the annual sunburn, right? Oh, Hey, it's holiday time. Let's go to Ibiza and come back with a lobster red bird. And that actually occurs a lot. So yes, the risk of skin cancer because of that behavior is going up. Okay, but if you take generally, it's still less sun than someone in Queensland would get. If you live in the Gold Coast, Oh my God, at nine o'clock, the UV index is sitting at five already. So it's, you're really being smashed by UV light. So there's just so much of it in Australia. It's never, the UK will never ever get to that stage. Okay. The second question is, has public health campaigns like the SunSmart SipSopSap campaign actually helped? And the answer is yes, it has. I know certainly that already data has come in certainly over the last few years showing that the rate of skin cancer amongst the younger population has started to plateau and fall. That corresponds with 20 years of sun protection message getting through. So they're getting less sun and so as, uh, adults age 40 and under, the rate of melanoma is actually dropping. Okay. So it's brilliant. Unfortunately, because the population is getting older, the rate of melanoma overall is still increasing, particularly in the older population, but the, we have the best. Public health, sun protection campaign in the world. We're seeing this gold standard. Now I

saw or listened to our program where they talked about the amount of sunscreen you're supposed to put on and almost talking about putting on a lot more than everyone thinks you need to put on as well. And like, what would you recommend about how thickness you should put it on

then? Yeah. Okay. Okay. This is how not to use sunscreen. Okay. How not to use sunscreen squirt a little bit on, okay. A little bit like, like toothpick size and then just try to spread all your face. And just apply it once, let's say at 10 a. m. and then stay in the sun for the next eight hours. Okay, so, lots of issues there. The first thing is, you're not getting a high enough concentration of the sunscreen. The second thing is it'll wear off. So it's actually doing sunscreen wrongly is almost as bad as not using sunscreen. Okay. So people just put a little bit on the abs and get cool. So we recommend number one is that if you're going to use a sunscreen, you're going to put enough of it on, and that's like a teaspoon for the whole face. Teaspoon for your arm, for your forearm, a teaspoon for your body, but for your upper arm, teaspoon for your chest, two teaspoons for your back. So it's quite a lot of sunscreen you need to use. And then the second thing is that you actually need to reapply it every two to four hours depending on your physical activity. So if you're putting it on and then you're going out, you're swimming, you're tiling yourself off, you're going to wipe the sunscreen off and you need to reapply it every two hours. Third thing, never use sunscreen by itself as the sole source of sun protection. So combine it. So you use sunscreen, wear a shirt, wear a hat, sunglasses and seek shade. So if you do all that's much better sun protection than just using a little bit of sunscreen once a day. Okay,

where does Merkel cell carcinoma come

into play? So Merkel cell carcinoma has been around for a while. And it just basically shot into prominence because there's a, an American musician called Jimmy Buffett who just died. He's a guitarist of some reputation. Okay. And he basically, he died of a Merkel cell carcinoma. And so suddenly the internet's all over. What is Merkel cell carcinoma? So this is a very unusual, uh, type of non melanoma skin cancer. It is actually caused by a virus called the polymyoma virus. And it's more prone in people who are immunosuppressed. So if you're immunosuppressed, let's say you're a transplant recipient, the rate of Merkel cell carcinoma goes up like 50 times. And it is induced by the sun. And it is pretty deadly if it's picked up late. Okay, so if it's picked up late, it can metastasize a bit like a nasty, thick melanoma. Nowadays the treatment is excision and radiotherapy. And that, that actually does quite well, but it is quite rare. I would see maybe one case of Merkel cell carcinoma every five to 10 years. It's quite rare. So it's

actually caused by a virus then. So one of the advantages of having the COVID era is the development of new vaccination techniques. Do you think RNA vaccinations may have a role for these sort of things in the future then? Look,

I, certainly the kind of, the role of vaccination against cancer is, the most remarkable story is cervical cancer, okay? Where you have a vaccination against these HPV types, which are very oncogenic and it's absolutely smashed the cervical cancer rates all over the world. It's now so much lower than it used to be. It is remarkable. It's a great story. There is a, an association of squamous cell cancer, the skin and certain HPV types, but it's not so clear cut. They're not like in cervical cancer where you have, this sort is very oncogenic. And so if you vaccinate against that, you wipe it out. Unfortunately, there are 150 to 200 HPV types and some of them are involved in skin cancer. But there is actually quite a lot of research going on currently looking at which HPV types are associated with skin cancer. And hopefully somewhere down the line, we may be able to vaccinate against some of them. Somewhere down the line. Wow.

Speaking of the Gardasil, has that decreased the incidence of warts that people have got on their hands and children get on their

hands as well? No, there's, there's no good evidence, but there's a lot of anecdotal evidence where Patients with multiple viral warts have had Gardasil vaccine injected into the warts and they've cleared. It is still in the realm of anecdotal evidence. If your back's to the wall and you've got a patient with multiple viral warts and you've done everything and you can't get rid of it, then potentially you can give these HPV vaccines directly into the warts. It has been done. Because all of

those warts disappear on their own anyway, don't they, on the ones on the limbs

and things? Not always. You have those that just hang around for years and years. You have some that disappear on their own, and then if you have an immunosuppressed patient, for example, a transplant patient, and they have a viral wart, it never goes. Almost never. You stop the immunosuppression, they go. If you're on immunosuppression, they don't go.

It's been fantastic talking to you, Alvin. It's been a fantastic ride, listening to your whole story about spot diagnosis. Tell us a little bit about yourself, just before we finish up. What brought you down this whole process of education and, Where you come from as well.

Thank you. So, uh, my background is Malaysian Chinese. I grew up in Singapore and I came to Australia in, um, 1986. And then after VC, I went to Melbourne university medical school and, uh, I was trained at St. Vincent's, uh, clinical school. And when I was an intern, I did a, when I was in medical school, I didn't want to be, I want to be a psychiatrist because it was fascinating to me. But the first job I did was actually as a dermatology resident at St. Vincent's. And I was mentored by some brilliant dermatologists, Professor Robin Marks, Dr. Harvey Rothstein, and they were really encouraging. And I found dermatology absolutely brilliant. This is the most critical of all of medicine, I think, because in what other specialty is the organ affected right in front of you? Right? So you're an orthopedic surgeon. You still need to move joints and. And look at x rays and MRIs, well, we just look and feel and it is all there. It is all there. So very interesting for people who are very visually minded, like myself. Dermatology is great for people who are visual, who like pattern recognition. And that's basically what I trained in. And it's been a great journey. There are some of us who are just educators, pedagogic. And, uh, I found myself in the space of teaching more and more. I was an examiner for my college and I've been teaching at my hospital for, since I actually became a dermatologist. And so spot diagnosis is like a natural progression of how can you actually teach a lot of people about something that you're passionate about? I think actually a podcast is not such a bad idea. As you found out, it was brilliant to hear. And thank you very much. It's a real pleasure. Thank you for having me.

Thank you, Associate Professor Alvin Chong from Spot Diagnosis and from Victoria. Thank you very

much. All right. Thank you.

Thank you very much for listening to our podcast today. I'd like to remind you that the information provided is just general advice and may vary depending on the region in which you are practicing or being treated. If you have any concerns or questions about what we've discussed, you should seek advice from your General Practitioner. I'd like to thank you very much for listening to our podcast, and please subscribe to the podcast for the next episode. Until then, please stay safe.