A Skin Cancer 101. Roundtable with Ade Adamson MD and David Whiteman PhD

0:10Ade Adamson MD: Welcome to the ECO-L podcast. This is a show about the science of cosmetics. My name's Jen and I'll be your host. This episode features a roundtable on skin cancer featuring two prominent skin cancer researchers, epidemiologist Dr. David Whiteman and dermatologist Dr. Ade Adamson. What are the knowns and unknowns? What should people know? And what are the widespread misconceptions? Spoiler for the convo, some of these misconceptions are even common amongst dermatologists. You might be surprised by some of them, especially when we're talking about skin cancer rates among skin of color. Before the episode, this past weekend, we hosted the Truth in Beauty eSummit, a full-day free eConference dedicated to unpacking misinformation that's impacting the cosmetics industry.

1:03Ade Adamson MD: If this is a topic you're interested in learning more about, I'm not sure you'll find a more comprehensive spot. The replay is now live, which you can find at theecol.com. As always, thank you so much to my Patreon supporters for supporting my SciComm work, including this podcast. You've been a big part of my motivation that's kept this show on the air for so long. Thank you so much for your support. If you'd like to support my work on Patreon and it's accessible, you can find me at patreon.com slash the eco-elm. Other great ways to support this podcast is by subscribing to it on whatever platform you're listening on, writing a review for the podcast if you haven't already and sharing.

1:45With that, here's the episode.

1:50Ade Adamson MD: I'm here with Dr. David Whiteman and Dr. Ade Adamson, and we're going to have a roundtable about skin cancer. There is a lot to it, so I'm just going to get right to my first question. So my first question, can you give me a 101 on what skin cancer is and the different types of skin cancer. David, would you like to start those? Sure. Well, I'll defer then to my esteemed dermatology colleague who will give you a more precise answer. But skin cancer is not one disease. It's a catch-all name for multiple different kinds of cancer. The most common types are the keratinocyte cancers, which arise from the most common cells in the skin, the ones that make our body lining.

2:37Ade Adamson MD: So we have basal cell cancers and squamous cell cancers or carcinomas, more technically. And then we also have melanomas, which are less common, but typically more aggressive. And they arise from the pigment producing cells in the skin, the skin that makes our skin tanned and coloured. And they're the three most common types. And then there are other rarer kinds, Merkel cell carcinomas and various kinds of lymphomas that arise from different cells that reside in the skin, which is a very complex organ. That's a brief 101, I hope. Most skin cancers arise following exposure to sunlight, typically, that's the most common pathway.

3:13Ade Adamson MD: And they're usually visible on the skin and treated by people like Ade, dermatologists who are experts in diagnosing and treating these conditions. Ade, what do you have to add?

3:24David Whiteman PhD: Yeah, I would say that's an excellent summary. And I would say is that oftentimes when we talk about skin cancers, we don't always necessarily differentiate between these buckets. And it's very important to differentiate between those buckets. One, because of the strength of the relationship between sun exposure and these various types of skin cancers, as well as the potential lethality of these different types of cancers. And the other thing I would say is that how we track these various subtypes of skin cancer is very different, at least here in the United States, and I think also in Australia as well.

4:01Ade Adamson MD: Based on our current understanding, how does skin cancer happen and how does that vary depending on the type of skin cancer? How much is known versus unknown? Aday, do you want to start this?

4:17David Whiteman PhD: So the most important modifiable risk factor for the development of skin cancer, as David mentioned, is sun exposure. There have been many, many epidemiologic studies and molecular studies showing that relationship. And I would say that relationship is strongest for keratinocyte carcinomas, namely squamous cell carcinomas and basal cell carcinomas, but also for melanomas as well. Although I would say the relative risk, the strength of that association is weaker, but it exists and it is consistent in epidemiologic studies that have been done over many, many decades. I don't know if David thinks that's a fair...

5:02David Whiteman PhD: I agree 100%.

5:03Ade Adamson MD: You've absolutely explained it. Skin cancer is largely driven by sun exposure, but there are other environmental factors for some of the skin cancers. Some exposures in the environment like arsenic, which is in contaminated drinking water in parts of the world, can lead to squamous cell cancers, the SCCs. And there are some medications, some of the immunosuppressive medications that people take, you know, post transplant or for treating other inflammatory diseases, these suppress the immune system. And we know the immune system now has a very strong role in controlling the development of skin cancers.

5:39Ade Adamson MD: So our immune system, it seems, is constantly keeping these things under check in our body. And when we lose our immunity or parts of our immunity, these skin cancers can become quite florid. And people who have transplants, unfortunately, suffer rates of skin cancer that can be hundreds or even thousands of times higher than the general public. So that's increasingly a common cause of skin cancer as more people are candidates for transplantation and survive for long periods after transplant. So it's a sizable component of the skin cancer problem now in advanced countries, in industrialized countries.

6:18David Whiteman PhD: And I would say that we have also harnessed that fact in the development of new medications, i.e. immunotherapy, which harnesses the immune system to attack skin cancers, most notably melanoma. I would say that immunotherapies have really made a dent in our ability to have a durable response and increased survival for people that develop metastatic melanoma.

6:43Ade Adamson MD: How does this vary depending on other factors, for example, skin color? And then for that, how much is known versus unknown? Ade, do you want to start again? Yeah.

6:58David Whiteman PhD: So I'm going to start this off and then I'm going to let David fill in the blanks because he's been at the forefront of trying to figure out who is at highest risk of developing melanoma specifically, and how can we target those people for potential interventions to improve outcomes? So there are other factors that are really strongly related to the development of skin cancer. I would say the number one factor is age. I mean, that's the number one factor of developing cancer in general. Being of a European ancestry and having, you know, type one fits back to skin, so really light skin, tendency to burn.

7:38David Whiteman PhD: Having a lot of atypical moles is also a risk factor for development of melanoma in particular. Having red hair, light eyes, all of these factors contribute to an increasing risk of developing skin cancers.

7:57Ade Adamson MD: Ade mentioned the importance of ancestry and heritage, and that manifests mostly as pigmentation in the skin, degree of pigmentation is a very strong protective factor for skin cancer and we know just from historical data that melanoma really is a disease that is common only amongst European ancestry populations and particularly when they have migrated from their place of origin in sort of cloudy subpolar northern Europe and migrated into places like Australia, New Zealand, South Africa and the United States where there is far more ambient ultraviolet radiation and so those skin types are just poorly adapted for that environment and that's why they're unprotected and that manifests as skin cancer in middle and late age whereas people who trace their ancestry to those more tropical and equatorial regions are more deeply pigmented.

8:55Ade Adamson MD: The pigmentation varies a lot in those populations around the world but But it seems to be, regardless of the extent of pigmentation, just having more than Europeans is very protective. Even within Europe itself, the populations in the Mediterranean, so Southern Europe, Middle East, North Africa, are far more protected against the sun. So it's really the absence of pigment that is very harmful. the presence of pigment seems to be protective almost regardless of the abundance. That's not quite true. That's an oversimplification. But absence of pigment is a definite risk factor. So people from ancestrally from Ireland, Scotland, Northern England are particularly vulnerable.

9:40Ade Adamson MD: They have very low ability to produce pigment. And that means their skin cells are unprotected. And when they are exposed to sunlight, damage occurs, and that leads to the skin cancers.

9:52David Whiteman PhD: And I want to say something, you know, I guess maybe slightly controversial. And I think it's an important point, which is people will often say, you know, it's purely about how light you are. And that if you're light, say, but from, say, East Asia or you're lighter and say from sub-Saharan Africa, that it's just all about the lightness. But melanoma rates, say in Japan, where there are folks that are very fair complected, is really low there as well. And so I think it's more than just pigment. It's pigment as well as ancestry. And as David pointed out, melanoma in particular, and I would say skin cancers in general, are primarily a disorder that is dominant in people of European and Northern European ancestry.

10:42Ade Adamson MD: 100 % agree. Yeah. I find that very interesting considering the conversations that I feel like maybe are dominant in the North American space. I'm not sure how they are in other areas of the world, but as an example of some of the dialogue that I see, it's in cosmetics, cosmetic sciences, and in the dermatology community from like the personal care products council or the American Academy of Dermatology. I've seen similar statements from this, but I just pulled up a blog from the PCPC about sunscreen and they advocate for people, everybody, to wear sunscreen every day regardless. And so they have a myths first facts section that I would be interested if you guys feel that perhaps there may be a problem with the commentary.

11:41Ade Adamson MD: Myth. Skin cancer is a problem, a rare problem, that only affects older or fair-skinned people. Fact. One in five Americans will develop skin cancer by age 70. Myth. People of color cannot get skin cancer. Fact. Skin cancer accounts for 1 % to 5 % of all cancers in people of color with varying rates across different groups, 1 % to 2 % in Black people, 2 % to 4 % in Asian people, and 4 % to 5 % in Hispanic people. And then they go on to say, sun safety is not seasonal or optional. Protect your health and wear sunscreen.

12:25David Whiteman PhD: Do they have citations for some of these things? Or these are just broad claims? They do not. These are broad claims.

12:30Ade Adamson MD: I think they might have other commentary elsewhere that is cited, but there was no citations on this page. I'm sorry if I'm being unkind to PCPC for not finding citations that you've cited somewhere, but there was no citations on this page.

12:43David Whiteman PhD: Well, I mean, I can start off is because I'm in the fray on social media as it relates to all these arguments around who should wear sunscreen, for what reason, when they should wear sunscreen, I would say in the broad strokes, in the United States, at least, we have a difficult time with our, I guess, governing bodies, say the American Academy of Dermatology or American Cancer Society and others. In framing some of these problems with nuance and being very kind of precise about the data, we almost feel like we need to be simplistic, even if it's incorrect, in order to perhaps benefit the largest amount of people possible.

13:31David Whiteman PhD: But I think that that is a risky way of going about public health messaging, because if it seems, or at least by the data, it's obviously incorrect for certain groups, you might decrease trust in populations when it comes to listening to public health messaging. I know Australia has a way more nuanced kind of recommendations that relates to sun exposure and sun avoidance. And I mean, I think David can speak to that. He's been involved heavily in those guidelines.

14:04Ade Adamson MD: Yes, I've actually just popped those guidelines in our chat here, Jen. But yeah, this is a very contested and controversial space. But it's very clear that rates of skin cancer do vary by ancestry. There's no doubt about that. The gradients are very clear in all populations. especially in populations like Los Angeles and Auckland in New Zealand where there's good cancer registration data and it captures it the registrations are captured by ancestry or by race and you can see that there's a you know a sort of quantum leap in the in the incidence rates of skin cancer amongst people of European ancestry or white ancestry compared with other ancestries So yes, people of colour can definitely develop skin cancer, but it's not common.

14:49Ade Adamson MD: It's not a primary cause of morbidity or mortality. And it doesn't appear to be rising in those populations. There doesn't seem to be an unbalance over historically what's occurred. But that's not the case in white and European ancestry populations living in low latitude countries, but also increasingly in Europe as well. And that's a whole different behavioral pattern over there explaining their rates of skin cancer. But there are there are different rates. So in Australia now, recognizing that people actually do need a little bit of ultraviolet radiation to produce vitamin D. we have pockets of the population in parts of Australia who have very low vitamin D levels for parts of the year and in fact you know this can be consequential it can have adverse health effects in its own right so the recommendation now in Australia is more more graded so for people of type 1 type 2 skins that burns and does not tan basically people of Celtic ancestry they're advised always wear sunscreen.

15:55Ade Adamson MD: When the UV index is three or more, always wear sunscreen every day. For people with skin types three or four, which is more tannable skin, they're advised to wear sunscreen when they're outdoors and the index is greater than three. But there are occasions of the day when they might go out without sunscreen or sun protection in order to generate vitamin D. And for people with skin types five or six, darker skin types that rarely burns and is always pigmented, they're advised to be more able to go out into the sun. So it's quite a nuanced message. It's a lot to package. It's very hard to get that out as a public health strategy.

16:33Ade Adamson MD: And we're grappling with that complexity now. But anyway, there's a position statement that clinicians and health policy people can review. It contains the evidence and the reasons behind making those recommendations. But the challenge is communicating that to the public. It's a very difficult message to get across, you know, how much sun is enough, how much is too much. These are really difficult messages to get across. So we're working our way through that process now.

17:01David Whiteman PhD: You know, David, I mean, in struggling through that, you know, we're at the opposite pole here in the States. Do you think that's, do you think it'd be better if, you know, in Australia you were, you know, you had more of just one size fit all, just kind of messaging? Or do you think that it's, that's also counterproductive? Because I don't know what the answer is. And, you know, that's something that I struggle with when I talk about this in public.

17:24Ade Adamson MD: Yeah, look, it's a really tough one. And I, my position on this vacillates because the arguments from both sides are compelling. But there are, you know, in Australia, there's pretty good sun protection programs in schools. So most schools in Australia will have a no hat, no play policy. Kids will be instructed to not go out into the playground at recess or at lunchtime unless they're covered up against the sun. And so increasingly though in Australia, like in many countries, we have people from all over the world in large populations. So in Melbourne, in Southern Australia that has a relatively high latitude and low sunlight in summer, we have kids from Sudan and other places with very deeply pigmented skin who are now becoming vitamin D deficient and at risk of bony metabolism problems because their vitamin D is too low.

18:17Ade Adamson MD: And for teachers to be saying to those kids, you need to cover up out in the sun is kind of not in their best interests. But it makes it hard for teachers if some kids are not allowed not to wear a hat and other kids must wear a hat. It has overtones of all sorts of bias. So these are really difficult policy decisions and settings to get right. And especially in, you know, educational settings where kids are vulnerable, it's a really tough one. So we're going to have to work this through and find a mature way to land on a position that has the best interests of the development of those children at play, but also, you know, protecting them from all sorts of stigma and other things.

19:02Ade Adamson MD: So it's a tough one.

19:04David Whiteman PhD: And I mean, I can even put it more, you know, plainly. Here in Texas, there are also some schools and daycares that practice photo protection, you know, telling parents to send their kid to school with sunscreen or, you know, hats, etc. And, you know, quite frankly, if you have different recommendations, that might be the, you know, a four-year-old's first entree into what race means. Yeah, exactly. And what difference means. And, you know, that's a heavy thing, you know, for a parent to have to think about, you know, go through the kids themselves and their relationship. You know, in, you know, teaching, you know, is my biology different than, you know, my other classmate or what else is different about us?

19:48David Whiteman PhD: So I want to at least kind of say state that plainly as a specific example of. No, I agree with you. 100 % or not.

19:57Ade Adamson MD: We're balancing psychological safety, physical safety, and I'm not an expert in those things. So that's where the educational and policy people have to just work through the evidence and land on what's best. But I would be hopeful that we could find a way of navigating this. It shouldn't be insurmountable, but people are people and it gets complicated fast. us.

20:22David Whiteman PhD: So what I'm hearing from you then is a one size fits all you don't think is the right approach?

20:27Ade Adamson MD: Well, for adults, that's our recommendation. We specifically exclude children from this recommendation. Because of these issues, we quickly realized from all the feedback and advice that it was going to be a more complicated thing. And in fact, in early childhood, you know, it's a particularly vulnerable time for skin cancer as well. So maybe a one size fits all is better. But So our advice, and I'm glad you pushed me on that because our advice is specifically for adults. That's where people have discretion and, you know, they have agency and they can hopefully make decisions.

21:02David Whiteman PhD: But it's even more difficult because if we think about risk factors for developing, particularly melanoma in the future, it's like childhood sunburns and sun exposure that is like so much more, you know, important, you know, so. Yeah.

21:18Ade Adamson MD: So it's a challenge. And you're right. We know the science is pretty strong, very strong on the importance of exposure to the sun in childhood for future risk of melanoma. That's a key, key time to protect kids. Now, you had mentioned that people of color also get skin cancer. Is that related to sun exposure? I'm saying this also with a lot of the narratives that I've heard among skin professionals talking about a lot of people use Bob Marley as an example of like, yeah, black people also get skin cancer. You need to wear sunscreen. And that seems kind of stigmatizing and like not, I mean, like, was that related to sun exposure?

22:08Ade Adamson MD: Thoughts?

22:08David Whiteman PhD: I mean, he had it on his toe or like under a toenail. I mean, when was the last time you had a sunburn on your toenail? I would say that he has trotted out all the time. And yes, he's developed and passed from a melanoma type of skin cancer, but it wasn't sun related and sunscreen would not have saved his life. And I think it's unfortunate that his diagnosis gets misused in that way because it kind of distracts from perhaps us finding reasons why folks of color develop melanoma, as an example. UV exposure does not seem to be an important risk factor in non-European populations. Full stop. Now, if you get into non-melanoma skin cancer, keratinocyte carcinomas, specifically in Asian populations, there does seem to be a relationship.

23:01David Whiteman PhD: It's much weaker than in European populations. But I've done a systematic review looking at this, and there is some data supporting it for keratinocyte carcinomas, although the data is kind of, I would say, mixed.

23:17Ade Adamson MD: Yeah, and Jen, right at the outset, we said that melanomas, in particular arise from the pigment cells of the skin, but those pigment cells are also found in other parts of the body that are not on the skin. So on mucosal membranes, inside our gut, inside our reproductive tract, at the back of the eye, even in the brain, there are pigment cells and they're derived when we're an embryo from the neural crest. So they're related to nerve cells. And so occasionally those cells, for reasons we don't know why, become cancers. They become malignant and they undergo transformation and they become a cancer.

23:59Ade Adamson MD: It's not related to sun exposure. Whatever drives the development of those cancers remains largely unknown. They're very rare and they occur in human populations throughout the world at about equal frequency. So it doesn't matter if you're black, white, Asian, Hispanic, those ones appear to arise at similar low frequency. And so though amongst people of colour, they're the melanomas they get. They don't really get melanomas of the skin where Europeans get them when they're exposed to the sun. So it looks like they can be common amongst people of colour. But in fact, it's just occurring at the usual frequency, but there's no other melanomas arising in that population, in those populations to compare with.

24:46Ade Adamson MD: So that's why Bob Marley was just really unlucky. And in fact, now in the modern era, this century, this decade, there's been a lot of work untangling the DNA sequence of these tumours, these acral melanomas and plantar melanomas. And they carry a totally different mutation profile from the ones that occur elsewhere on the skin. And the ones that occur elsewhere on the skin have UV signature mutations all the way through their genome, peppered with, you know, like a shotgun has gone through and peppered the genome with hits from UV. The acral melanomas of the kind Bob Marley had, they have a different profile, not related to UV exposure, no evidence of UV damage causing them.

25:30Ade Adamson MD: So we do know they're a different type of melanoma. We just don't know why they arise. That's an unanswered question.

25:37David Whiteman PhD: And that's unsettling to a lot of people, you know, because a lot of people, well, why, why, why, why? I mean, we don't know the reason why a lot of people develop a lot of different cancers, you know, brain cancer, certain types of breast cancer. Yeah, there's certain environmental things that can increase your risk, or if you refrain from certain activities, decrease your risk. But for a lot of cancers, we just don't know why.

25:59Ade Adamson MD: Michelle Wong had a few questions that I feel are kind of relevant to what we're currently talking about. The first question was, why are the guidelines so different between regions?

26:15David Whiteman PhD: Regions of the world, you mean?

26:18Ade Adamson MD: Yeah, well, I think I don't know why. People are people. Different countries, different jurisdictions, different groups of experts come together at different points in time, and they do their best under their own conditions and circumstances. I think they're all well motivated, but it is confusing for consumers and the public and clinicians when messages conflict with one another and different groups of experts can land on slightly different recommendations. Yeah, it's difficult and it can be a mess sometimes. But increasingly, I think what we're doing in Australia, and I know in other places as well, people are trying to find consensus frameworks and bring together these conflicting bodies and groups and work through the differences.

27:02Ade Adamson MD: Most of the things that agree on a lot, they're actually underlying the advice is similar, but the details can differ a tiny amount. And that's what people latch on to. So in the main, I would say the recommendations would be broadly very similar across most agencies and organisations. And increasingly, it would be nice to get a uniform set of guidelines. But you know, having said that, settings do vary. And in a place like Queensland, where I'm from, where the UV index is high all year round, we have to make our recommendations for the people living in our area and the patterns of exposure they have.

27:40Ade Adamson MD: And that will be different from what happens in Seattle or in Maine or somewhere where it's a different climate, different seasonal pattern, different UV exposure rates. So there will always be settings that come into it. And that's just by dint of the environment in which we live. I would think that you would be more conservative with suggesting people wear sunscreen every day kind of messaging compared to in the States or Canada with the broad recommendation of you need sunscreen every day. Well, I would think that where we've landed right now in Australia, our consensus statement, which brought together 14 different organisations, dermatologists, general practitioners, cancer councils, endocrinology society, bone and mineral society, public health society.

28:29Ade Adamson MD: So we brought everyone together into the tent. And where we landed was making it based around the UV index, which is an absolute measure. doesn't matter where you live, you can measure the UV index. When the UV index is three or higher, wear sunscreen. On all days when the UV index is forecast to be three or above, wear sunscreen. So you can give that advice in Seattle or Alaska or in Queensland or in Tasmania. That advice remains the same because the UV index can be measured in all of those places and can be forecast very accurately. And so you can give people advice based on the UV index. Now, people quibble about whether three is the right threshold and the data underpinning that decision of three is shaky at the moment but it is a very defensible position that's a low a fairly low level of uv irradiance and so it takes quite a while for the skin to demonstrate any adverse effects at uv index three.

29:31Ade Adamson MD: So that will be like a spring morning in many parts of the US, late spring. So anyway, the point being that if we focus on the UV index, which is a very measurable quantity, then the advice will hold all around the world for people of high risk skin types.

29:51David Whiteman PhD: You know, I, to Michelle's question about, you know, why is it so different? At least, in the States, I can't imagine that many interest groups coming together to make a recommendation around skin cancer prevention. I think that Australia, for whatever reason, skin cancer is such an important cancer that just the general public cares about so much, way more than I would they do in the United States. And their public health system has come together around this. I mean, they even had the massive slip, slap, slop, slip. I'm going to forget all of the terms since the 80s for skin cancer prevention.

30:43David Whiteman PhD: And just that level of organization and buy-in from the public is just way different. And I think that's one of the reasons why you can get buy-in whereas it's a lot different in the state. And we're also, I think, we are a much larger country. So it's harder to kind of get your arms around public health in that way.

31:05Ade Adamson MD: Yeah, I'd agree. There are benefits in being a much smaller population. There are just fewer heads to knock together, really, to bring everyone together. It must be very difficult in a mega country like the United States. I'm wondering, Ade, in your experience, I don't know if my observations on social media would be the same as your experience within the dermatology community. And my observations within the cosmetic science space and cosmetic science professionals, sunscreen professionals and dermatology professionals. Do you find that you get more pushback on your commentary that there are differences in the impact of sun and how that relates to skin cancer for different skin tones?

31:57Ade Adamson MD: Do you feel that you get different reactions depending? Like I feel like this conversation is like accepted in Australia, but I don't know if it is in North America, at least like in the cosmetics science space, sunscreen space. The convert that's I mean, I think you're kind of an outside perspective from the things that I've heard in that space. So, yeah. What's your experience there?

32:24David Whiteman PhD: You know, I started, I guess, talking about this on social media, writing articles for popular press, et cetera, six, seven years ago. And at that point, I thought this was a silly conversation to have because it's clear. Like if, to me, if you have two eyes, you read a little bit and even in clinic, or if you just think about who you see that has skin cancer, develops it, dies from it. It is disproportionately one group. And so I was quite astonished by the pushback that I got initially around me saying that UV exposure is not really an important risk factor for the development of melanoma and skin cancer in most populations of color.

33:09David Whiteman PhD: But I feel like that stance is, from my colleagues at least, has softened a little bit over time. I'm seeing more people talk a little more nuanced around it. Yet the American Academy of Dermatology really hasn't formally changed its stance. There was a moment in time where I thought perhaps they would take a stand on it, but not to the level that they have in Australia. And I would say now the fact that there's still some dermatologists that really feel like we need to be promoting UV protection for folks of color for cancer prevention is simply astonishing to me. And especially coming from dermatologists of color.

33:54David Whiteman PhD: It actually is mind-boggling. But, you know, people believe what they want to.

34:02Ade Adamson MD: Do they keep up on the research? and do they know how to critically appraise the research? I don't know. I just see some things in certain derms and I don't know if I'm just seeing things in influencer derms, but there seems to be some gaps in their ability to critically appraise research. Is that something that is within the training of a dermatologist? I don't know. What's causing that?

34:35David Whiteman PhD: Sorry, you don't have to answer that. Look, I'm not going to throw all of my colleagues under the bus. What I would say is it's hard to keep up with the research. And it's also hard to change your mind if you've been taught or you think a certain thing for, say, a decade or a generation or since you've trained. And to then all of a sudden change course, I think sometimes can be difficult for folks. I would also say that there's a faction of people that think that we have to be able to recommend something to people. Recommending nothing just feels like wrong, right? And there's also others that say, well, what if there's just more evidence out there that we need to collect?

35:24David Whiteman PhD: And there's just not enough studies yet. So we need to do the safe thing and just blankly recommend for everyone because we just don't know at this point. That's kind of where I land on my colleagues and how they think. But my counter to all of that is, well, we've done a bunch of observational studies of the same quality that we use to make recommendations in European populations. And in those studies, they've shown no association. You should feel comfortable in leaning into that data, but some people are unconvinced.

36:00Ade Adamson MD: I had another question for Michelle. A handful of U.S. germ fluencers seem to be finally taking on board some longtime Australian messages. Layer your sun protection, check UV index. There are benefits to sun exposure, but a lot of them are getting it kind of twisted. I've seen things like visors with no scalp cover getting really popular. If you wear protective clothing, you don't need sunscreen. These are quotations she's seen from dermatologists. You only need protection if the UV index is very high. Exposing your forearms to the sun for 15 minutes is enough for vitamin D with no reference to UV index, etc.

36:44Her question here is,

36:46Ade Adamson MD: what's the best way to educate medical doctors about all of this?

36:51David Whiteman PhD: So I'm going to blame the people that make guidelines, okay? The governing bodies, the people that are responsible for basically setting the tone for messaging. I think oftentimes physicians in general lean in on guidelines to determine what they feel like is representative of current evidence and not, because it's hard to keep up with, you know, the literature changes, it seems like, you know, every single year. And I think that if we were like Australia in that way, and, you know, actually had a more nuanced kind of messaging, say from the American Academy of Dermatology, for which I'm a member, okay, they might not like these statements, but I think that it would go a long way in terms of helping the rank and file dermatologist to really have something to point to as to how to counsel patients in the public.

37:52Yeah.

37:52Ade Adamson MD: And I know how these guidelines get developed and it is like making a fight.

37:57David Whiteman PhD: It's like a food fight or something.

38:01Ade Adamson MD: Guideline development is a very complicated process. There's always different stakeholders. Everyone's got an opinion. There's always one little bit of evidence pointing in a different direction and people want to be able to make sure that doesn't get lost in the wash up. So they're never perfect. I agree with Ade. I think clinical judgment and clinical assessment of patients in front of you is really important when it's one-on-one clinician, consumer, clinician, patient. Where it gets really hard is when you're doing public health strategies and you're trying to distill these really quite complicated science into messages that resonate with different target audiences.

38:39Ade Adamson MD: And that's a whole different ballgame. And I think often with guidelines, we're trying to do two things. We're trying to help clinicians talking one-on-one with their patients where they're making an individual assessment of that patient, what their risk is, what their exposure profile looks like. And then guidelines are also used for a mass media campaign or social media blitz. And, you know, it's not really fit for purpose to try and do both of those things. And that's the pickle we're in really is, you know, the science is complicated. Like many things in life, a little bit of something can be good for you.

39:15Ade Adamson MD: But that little bit is quickly exceeded by what happens in the environment. You know, we need a little bit of salt in our diet, we need a little bit of sugar, we need a little bit of fat. But it's really easy to get too much of all of those things really easy and most people's problem is from having too much rather than not enough and it's the same with sunlight there's very few things like tobacco or radiation that are just universally bad and uv is one of those things we do need a little tiny bit we need it for vitamin d but people can twist that into saying you know you need to get out every day and you need to get your head exposed or your face exposed and that's when it gets really complicated.

39:56David Whiteman PhD: And then the alternative, people can compare UV to smoking, which is also ludicrous.

40:02Ade Adamson MD: Yeah. Yeah. So yeah, it's getting that balance on something that has both benefits and harms. And depending on who you are and where you live, that risk equation differs. you know that's the nuance another complicated area in question is skin cancer on the rise if so which skin cancers and what factors are contributing to these rates i don't know who wants to start this question so i'll leave it to you to maybe as the uh the epidemiologist the numbers guy, I can have a crack and then Ade can jump in and correct me where I'm wrong. But in many parts of the world where there are European ancestry populations, white skinned populations, rates of skin cancer are rising overall, particularly in older people, and they're rising rapidly in older people.

41:03Ade Adamson MD: But we are starting to see in Australia, New Zealand, and I believe in the US from the data I've seen that amongst younger generations, rates of skin cancer are actually falling. And the reasons behind that appear to be multifactorial. But if I can focus on those two different bits of the population amongst older people, certainly in Australia, US, UK, Northern Europe, rates are still rising relatively rapidly in older people. And here I mean people over the age of 50. And a lot of that is their historical sun exposure that they had back in the 1970s, 1980s, that's now manifesting here in the 2020s and it will keep manifesting into the 2030s.

41:46Ade Adamson MD: So those populations almost have a baked in risk of skin cancer that is going to keep rising for a while yet. Amongst the younger populations, it does seem rates are falling. There are differences in different parts of the world, but Australia, New Zealand, and I think US white populations, rates are starting to fall in younger people, probably as a consequence of just kids spending less time out of doors, more screen time, lower outdoor exposures, as opposed to any public health messaging. But we don't really know the answers for that. So I'm giving you a very complicated answer there, Jen. It's a two-speed epidemic that is manifesting differently in parts of the world.

42:27Ade Adamson MD: I'll pass over to Ade. He'll unpack that for you more, I'm sure.

42:30David Whiteman PhD: Yeah, this is an area of controversy. And am I overstepping David by saying I've been involved in stirring some of this controversy related to cancer rates going up over time?

42:44Ade Adamson MD: Yeah, look, yeah, there is a phenomenon, Jen, that is widely recognized called overdiagnosis, where we are finding things, the more we look, the more we find, and we're finding things that we call skin cancers now, melanomas and other skin cancers, that probably have always existed as a latent pool of cancers that just were going to sit there and be relatively dormant. but we look for them we find them and so now they get recorded as a new cancer diagnosis and they appear in our statistics and so rates are going up that's a a whole different well no it's not different but it's it's related to the epidemic of skin cancer but i would say we are seeing a rise though in the thick aggressive melanomas as well so melanomas that have burrowed deeper into the skin layers, you know, ready to invade other parts of the body, we're seeing those thick melanomas, the rates of those are rising, definitely in the US, and they're rising quite rapidly.

43:43Ade Adamson MD: So it's unlikely that overdiagnosis would be explaining those that those are typically faster growing aggressive cancers that will come to attention at some point, and often quite quickly. So they're rising in incidence as well. So there's a there's a rise in these very thin melanomas that probably aren't going to hurt anybody, and then a rise in these thick ones as well. So it is a complicated story yet again.

44:09David Whiteman PhD: Yeah. And I would say that, well, from the US perspective, you got, and I think also in our story, you got to unpack keratinocyte carcinoma, basals and squamous cell, and melanoma. I would say that for basals and squamous cell carcinoma, we don't track those using cancer registries. So our ability to actually really know how many keratinocyte carcinomas happen per year in the U.S., we actually have no idea. We know it's in the millions, many millions, but we don't have an accurate kind of amount. But for melanoma, because states have to, as a mandatory thing, have to report to cancer registries when a melanoma is diagnosed, we have a better, more accurate ability to track how much melanoma you diagnose over time.

45:02David Whiteman PhD: And in the United States overall, not thinking about age cohorts, in 40, 50 years, we diagnose sixfold amount of melanoma over time. And you would think if that were the case that we would also see mortality decline over that same period of time. And we actually didn't see that at all until the introduction of new treatments for advanced disease in around 2011. And you started to see a curve go down for mortality in 2013. So that's the kind of phenomena that David is referring to of we're getting better at detecting melanomas, but detecting melanomas that probably were of no clinical consequence.

45:43David Whiteman PhD: But the problem is once you've diagnosed a melanoma, whether it's stage zero or stage one or whatever, you have to treat it because you don't know what would happen if you left it untreated. But the problem then becomes we then believe that the way out of this is to screen more people, look harder. That actually can get us into some trouble. At least that's what I think. And some people, I don't know what David thinks about screening as a solution, at least.

46:16Ade Adamson MD: Well, I guess this leads really well to my next question. And David, you can comment on it then. Is there a risk of over-screening? Also, are some of the broader public health recommendations potentially problematic? For example, in the USA, there's a recommendation that I think everyone should get their molds checked by their physician at least, but is it by a dermatologist today? I mean, like to me, it's like, good luck, good luck getting into dermatologists.

46:51David Whiteman PhD: That's also true. I mean, there are not enough dermatologists to screen everyone. Even if you were to bracket age like only non-Hispanic white, 35 and up, there still would be not enough dermatologists that are practicing that could do that every single year. The other thing is that there's no official guideline for the recommendation of skin cancer screening in the United States. The American Academy of Dermatologists doesn't have one, The American Cancer Society doesn't have one. And there are actually very few official skin cancer screening programs, I would say, even in Europe. And there certainly isn't in Australia, at least that I know of.

47:27David Whiteman PhD: But obviously, David knows more about that than I do. And part of the reason why is because we haven't been able to reliably actually show a benefit to screening the general population in terms of reducing outcomes that matter, like mortality.

47:45Ade Adamson MD: Aday's right. Nobody's recommend screening for skin cancer currently, largely because we have no evidence that it improves mortality. There's no large scale trials showing that screening reduces mortality. Having said that, we do know that the thickness of a melanoma at the time when it's diagnosed is a very strong indicator of future survival. So if you diagnose a melanoma when it's thin, you have a much higher survival probability than if you diagnose a melanoma when it's thick. So based on that logic, advocates for screening say, well, it makes absolute sense to diagnose melanomas early rather than late, because we know that survival is correlated with thickness.

48:30Ade Adamson MD: As far as it goes, that logic is very compelling. The question we all have is, if you do a screening program, are you going to find those thick melanomas early? Or are those ones just going to grow so fast that in between your screening intervals, you might screen once every two years, you might screen once every year? Will we actually find those fast growing melanomas or are we just going to keep finding the slow growing ones, the ones that always come to attention anyway? which means you find more thin melanomas but you're not finding the ones that are killing people that's the question we don't know the answer to and so right now in Australia there's a what we call the roadmap there's a there's a process happening right now funded by our federal government reporting in 2028 I chair the expert advisory committee so we're still deliberating on all of this evidence but we're looking to see whether or not there is a case to be made for screening a group of people who are targeted as being high risk for dying from melanoma.

49:33Ade Adamson MD: And that work is still ongoing. We're sifting through all the evidence. We're doing various types of modelling surveys because we don't have randomised trials. So it's a very difficult question to answer. Made more difficult because there are actually such high rates in Australia of opportunistic screening where people will go to their family doctor, their GP or their primary care doctor and have their skin checked and there are thousands of doctors in Australia who are not dermatologists but are trained in skin cancer medicine. That's all they do all day, every day of the week. They're primary care doctors who have sub-specialised in the treatment and diagnosis of skin cancer and they diagnose the bulk of skin cancers in Australia.

50:20Ade Adamson MD: 80 % of melanomas and skin cancers are treated by GPs in Australia because it's so common and they're pretty well trained. So we have very high rates of opportunistic screening in Australia. Large proportion of the population is screened anyway in an ad hoc opportunistic way without any formal screening program. So whether or not we have a federal funded screening program remains an open question. And where, ask me in 2028, I'll be able to tell you what we found.

50:56David Whiteman PhD: In Germany, they, as part of policy, people that above 35 can have a skin cancer screening every two years. So that's one country that I know that there is, you know, some official policy around you being able to seek out skin cancer screening you know, as an intervention.

51:18Ade Adamson MD: Yeah, and that's a really interesting one, isn't it, Adai? Because they keep publishing findings showing it's made no difference to melanoma mortality in Germany despite having this program. And there was a paper just published, I think it was this week or last week in...

51:32David Whiteman PhD: Last week in JAMA.

51:33Ade Adamson MD: JAMA, yeah, it was in JAMA, yeah, and showing no benefit from the screening program. So again, Jen, these are well-intentioned exercises, but they may actually miss the mark. You know, screening's a hard thing to get right, and you've got to have high rates of participation and you have to be able to find the cancers that are killing people. Otherwise, you're just being busy doing work and not actually making the problem any better. So it's an appealing strategy, but the mechanics of it and the actual implementation of it is really hard. And it's very hard to demonstrate benefits, especially as we're doing so well, really, in melanomas in lots of countries now.

52:15Ade Adamson MD: The treatments are really getting very much better. And people are predominantly being diagnosed with very early stage melanomas anyway. So a screening program may not improve that at all. It's going to be a hard one.

52:28David Whiteman PhD: It'll just inflate the incidence.

52:31Ade Adamson MD: Yeah, of in situ melanomas and early thin ones. Yeah.

52:36David Whiteman PhD: The way that I like to think about cancer screening is this barnyard pen of animals that you're trying to keep caged. It's an analogy that was popularized by one of my mentors, Dr. Gilbert Welsh, where you think about cancers as three animals that you're trying to keep penned in. You got your birds, your birds you can't keep penned in because they fly away immediately. Those are cancers that are going to kill you, whether you have a screening program or not, because they're just so fast growing. Then you have your rabbits and, you know, rabbits will hop around and it's easy to kind of pin those in.

53:13David Whiteman PhD: Then you got your turtles. Your turtles ain't going nowhere. So you don't need to be pinning them in at all. And the problem is with a lot of cancer and particularly melanoma, there are a lot of turtles. There are a lot of turtles. And the more you go around trying to screen, the more you find these turtles and you slap the label of melanoma on people that never would have had that disease harm them in any particular way. And it's a really hard thing for, I think, the public to understand because it's so appealing to think if I just get checked, I'll find something early and then I'll be cured and my life will be saved.

53:57David Whiteman PhD: And it's appealing for dermatologists as well because you feel like this is something that you can do. You can save a life. I mean, there are even dermatologists online that brag about how many melanomas that they diagnose. diagnose. There's even this dermatologist that brags about having a Guinness Book of World Record for finding the smallest melanoma possible. Honestly, I cannot think of another cancer where clinicians actually see it as a badge of honor to find more of. And I would say it is difficult for me to watch on social media some colleagues that are so certain that screening works despite the of the general population.

54:40David Whiteman PhD: OK, I'm not talking about people that have bleeding moles and I'm talking about people that are high risk. I'm just talking about regular person who just wants their skin checked, that they just so believe that this will work despite there being no evidence to show it. And in fact, more evidence to point to potential harms associated with indiscriminately screening people.

55:01Ade Adamson MD: Yeah, I kind of wonder, as you guys are talking, if there is a side of this conversation of like what I see in so many other headlines related to rises of skin cancer rates just the fear-mongering and misinformation that goes along with it for the contributors and the way to mitigate it and yeah the potential harms as you were saying to people whether or not it's the people who are receiving treatment or just now people are just really afraid because skin cancer on the rise. We certainly don't want to make people less worried about skin cancer, though, in one sense, because skin cancer still kills a lot of people.

55:45Ade Adamson MD: Preventable cancer. There are people dying in far too many numbers from melanoma each year, and there are people dying from squamous cell cancers each year, and there are people badly harmed and disfigured by basal cell cancer. So at ANI, I'm not saying that people should not worry about skin cancer anymore. We're definitely not saying that. We're saying it is a really big public health issue. But our ways of managing the medical workforce and communicating this message, we need to be really thoughtful about the way we do that. Because we don't want to throw the baby out with the bathwater. We don't want to go back when people were dying in their tens of thousands from melanoma.

56:28Ade Adamson MD: You know, the new drugs are great and all of that. But they cost a ton of money. like they cost a ton of money and we would much rather those people had never got a melanoma in the first place so i think we would both be on record as saying prevention prevention prevention if we can find them early let's find them early but let's not kid ourselves that we are so smart as a society we can design a program that will find every melanoma before it ever becomes invasive because that's a really tough thing to do and as that i said there are some that are just bad from the get-go. There are just nasty, fast-growing lethal melanomas.

57:04Ade Adamson MD: And then what people really need to know is if you see something changing on your skin, get in and get it seen straight away. If there's something that wasn't there and is now there and you're worried, or even if you're not worried, but you haven't seen it before and it's been there for a little while, go and get it checked. Buy an expert and let them deal with it because those melanomas are potentially going to kill you and you need to find them. And, you know, that would be our message, I think, at a, we've talked about a lot of different things. People might think it's not a problem anymore.

57:35Ade Adamson MD: It's a problem. We need to fix it. And if we can't prevent it, we need to find them early and get them seen by experts.

57:43David Whiteman PhD: And I agree 100%, you know, that it is a problem and both can be true, that it is a problem. And also there are different ways of trying to address that problem, scaring the entire public and telling everyone to go get checked indiscriminately. I think we probably both agree that that's probably not the way to go. And also doing that has the potential of creating harm in limiting the amount of attention dermatologists can then pay to people that do have molds that are changing. In the United States, at least, wait times to see a dermatologist can be in months, right? And if somebody notices something on their skin, they got to wait three, four months to see a dermatologist.

58:31David Whiteman PhD: That is far too long, right? If the clinics are filled up with the worried well that don't necessarily need to be routinely screened for skin cancer.

58:42Ade Adamson MD: Now, I had a few audience questions that I think would be good to insert here. So the first one comes from my Patreon supporter, Connor. I'll ask this one first. Connor wants to know, what is the current evidence for topical retinoids as part of skin cancer prevention? Are they most useful as field therapy for existing photo damage and ectinic keratosis? Or is there, I'm sorry if I've mispronounced the word, not by space. Is there evidence that they alter earlier carcinogenic pathways like UV-induced signaling, abnormal differentiation, and so on before lesions appear?

59:23David Whiteman PhD: So I'm less aware of topical retinoids for cancer prevention or retinoids have been used in the prevention of certain keratinocyte carcinomas. They've been shown particularly in patients that are immunosuppressed to reduce the risk of developing subsequent skin cancers. but I wouldn't recommend them for the general population for a lot of different reasons. But if you're talking about chemo prevention for skin cancer, most of the data is in keratinocyte carcinoma. And from a topical perspective, there are various types of field therapy, 5-fluorouracil is an example of one. Photodynamic therapy is also an example of field treatment to help treat field cancerization to prevent the development of subsequent keratinocyte carcinomas.

1:00:14David Whiteman PhD: And there's also oral niacinamide in certain high-risk populations. Those studies were done in Australia. I don't know if David wants to comment on those or not. And that's also an area of, I would say, controversy. And to date, there have been no oral or chemotherapeutic medications that have been found for preventing melanoma, at least that I am aware. So I don't know what else David has to say in this space.

1:00:41Ade Adamson MD: Yeah, I'm not aware of any full melanoma and the niacinamide or nicotinamide studies, I wasn't close to those, but as you say, they were done in high-risk populations where people already had documented history of skin cancer. I think the evidence was that those, that intervention, the nicotinamide did hold at bay skin cancers and reduce the development of new skin cancers while people were on therapy. But once they stopped taking the medication, the cancers came back. So it seemed to be a suppressant, but not a, not a cure. They keep them in a holding pattern and they're not without side effects, those things.

1:01:19Ade Adamson MD: So yeah, we don't have perfect strategies. Primary prevention is the best if we can get that message out there. But that can be very hard when people are in middle age and they've already had the damage.

1:01:29David Whiteman PhD: What Dave was referring to is the OnTrack trial from 2015. It was a New England Journal of Medicine paper that did show reduction in the subsequent while-on treatment of keratinocyte carcinomas. The people in that population had a lot of skin cancer, meaning they had like a history of, you know, five to 20 plus skin cancer in the last five years, which is not your standard patient that may only have, you know, develop a few of them. But more recently, there was a retrospective propensity score matched study done in the veteran affairs population here in the United States that did show or suggest that even for patients that develop one skin cancer or have a history of one squamous cell carcinoma, but also if they are prescribed nicotinamide, that they have a lower risk of developing subsequent skin cancers.

1:02:28David Whiteman PhD: So that data is not randomized, right? So it's not gold standard, but that data exists out there.

1:02:36Ade Adamson MD: Another audience question comes from Testaholic. There's a lot of info on skin cancer prevention, but less about recurrence. After my basal cell carcinoma was removed at age 27, the only advice from my doctor was stay out of the sun. As a patient, I still find it unclear how proactive I should be. Should I get a photo finder each year and remove anything suspicious? Is there any safe amount of unprotected sun exposure? Supplements, DNA repair enzymes, laser, red light saunas, other low risk interventions. For someone with a history of skin cancer who wants to do more than the minimum standard of care, what preventative measures do you actually recommend?

1:03:25Ade Adamson MD: Also, I feel like basal cell carcinoma gets dismissed a lot because you will not die from it. But the scarring left behind is not something I want to repeat anywhere else on my body. Adai, why don't you take that as the practicing dermatologist here?

1:03:40David Whiteman PhD: I feel like I don't want to dominate the conversation. No, you're not.

1:03:43Ade Adamson MD: It's good. So I would say that unfortunately, we don't really have much better than photo protection. Prevention through going to see your dermatologist on a regular basis if you have a history of skin cancer because that increases your risk of potentially developing more skin cancers.

1:04:04David Whiteman PhD: It is something that is deeply frustrating. I know that there are some influencers and some dermatologists online that want to sell you concoctions that they say will reduce your risk. I would say for someone with just one basal cell carcinoma, I'm not really aware of anything that shows strong evidence to do that. I know there's that one plant in Central America that apparently if you crush it up and you put it in a pill and you swallow it somehow, you get some kind of photo protection on your skin. The data around that are really poor. And so it's not something that I necessarily suggest that people go out and get.

1:04:49David Whiteman PhD: But I don't necessarily think it will hurt if you use those kinds of supplements.

1:04:54Ade Adamson MD: Yeah, I would agree. I think your correspondent said she was 27, which is quite young for a BCC. So I would say that she should be aware that she obviously is a high risk phenotype. And therefore, the advice to protect herself in the sun would be one to take seriously. I think that would be the surest way of reducing future burden of BCCs and other skin cancers for a person who was susceptible. So it's good advice. I know it's not perfect advice and you don't want to constrain your whole life around this one thing, but it's a step you can take positively to do that. And I'm not sure that there'd be evidence for having photo finder every year.

1:05:34Ade Adamson MD: But I think clearly the one that she's already had diagnosed, she picked that up. So be vigilant. If you notice anything changing on your skin, get it seen to. But, you know, it wouldn't be something to overly concern yourself with or overly worry about. be sensible in the sun, avoid unnecessary exposure and look after your skin. Just look at it and look after it. If there are changes there, get them seen.

1:05:58David Whiteman PhD: And I think what the correspondent is asking is like, what are primary prevention and secondary prevention things that we can do? And the only primary prevention really is UV and then secondary prevention is trying to find things early. But I don't think photo finder is necessarily going to be that much better than, you know, just a usual kind of clinic visit to the dermatologist. Yeah.

1:06:25Ade Adamson MD: Another follower from Instagram asks, does diet affect how the sun interacts with the skin? For example, seed oils or processed food, does that translate to more likely sun damage? Well, I'm not an expert on this. Many, many people have looked at dietary and nutritional components in relation to risk of skin cancer, but also response to UV. I'm not aware of any compelling, consistent findings that would suggest that any of these things do offer more protection. We know there are certain classes of medications that do make you more photosensitive through known pathways if you're taking those medications your doctor will usually advise you that you know you will be photosensitive some antibiotics and some other blood pressure pills blood pressure pills mental health um other other other prescriptions but they usually come with the product label warning and people will warn you about that but as far as diet goes it's not my expertise i have to say but i i haven't come across anything where there's a consistent or compelling story.

1:07:36David Whiteman PhD: And if a skin cancer epidemiologist who spends their life thinking about how to reduce risk of skin cancer has not come across anything, it's highly unlikely that some random person on the internet... Nothing compelling. Right, that a random person on the internet is going to find something compelling that is of high-level evidence. Because, I mean, I could speak for me and David. We both want the same thing, reducing the risk of skin cancer in populations that are at risk or even at large. And whatever shred of evidence we can find to promote that, we would be all over it. And I would say the data around diet, yeah, it's not really compelling at all.

1:08:24Ade Adamson MD: I'm going to couple two questions together. Heather, what do you think are the biggest challenges with reducing the impact of skin cancer at the moment? And where do you see the most potential strides to be made? If I start, I would say that skin cancer really was a 20th century and 21st century phenomenon. If you go back in our history, people wore different kinds of clothes. They covered up, They didn't undress in the sun. They didn't seek the sun. People just got about and did their life, but they were covered up. And in that era, even in Australia and even in the US and New Zealand and South Africa, where European populations migrated to sunny environments, they were covered up and they did not get skin cancer at any great rate.

1:09:14Ade Adamson MD: And we've had good records in Australia on deaths from melanoma for nearly 100 years now. and you can see the rate started to go up in the sort of late 1940s 50s and they skyrocketed through the 60s and 70s and all of this really was cultural shift and people really worshipping the sun and getting out there so I would say it is possible for humans even with low pigmentation in high uv environments it is possible for people to live in those environments and not experience high burdens of skin cancer but it's it's a cultural change it's a population change it's all that's all primary prevention and there are really big gains to be made there we know theoretically it's possible but how we actually make that happen in the 21st century is a challenge but it's possible and that should be our goal and then in terms of secondary prevention that is finding the important cancers early that really takes individual vigilance I guess when you notice something on your skin that is changing that hasn't gone away and it's not just a pimple or a blemish or something it's a new and changing thing get it seen and be aware distilling a lot of stuff but be sensible in the sun and know your skin and those two things i reckon we could go a long way to reducing the burden of skin cancer of all kinds just because this is a popular conversation right now in the media, this conversation about misinformation related to skin cancer and sun protection.

1:10:52Ade Adamson MD: So yeah, what's our landscape look like to you? What should we know about the misinformation that is out there related to skin cancer? Well, I think there's a bunch of misinformation out there. And I honestly avoid trolling the internet because there's so much misinformation. But the stuff that I get put to me, I've seen dermatologists and others influencers who are advocating that people should be getting more sunlight rather than less sunlight and that sunlight's really good for you and that the hazards of sunlight have been over-egged in the population and I think these are these are you know harmful messages they're wrong we know that for people with fair skin types excessive exposure to the sun especially high intensity sunlight is really damaging.

1:11:42Ade Adamson MD: I mean, we at my institute, we daily are doing experiments on human skin samples, where you can just see the DNA damage. The human DNA is almost like a readout meter of how much sun exposure you've had. And we can see the damage in the skin. And it's not easily repaired or not always repaired. So we know that sunlight and the UVB spectrum particularly is very hazardous for DNA. DNA is very sensitive to UVB. So we know it causes skin cancer. So I think that that's a big bit of misinformation. And then there's a whole world of debate, discussion, information, whatever on sunscreens. That would be another podcast, I think, Jen, quite honestly, to unpack all of that.

1:12:27Ade Adamson MD: But there's a lot out there. Some of it is very unhelpful, I would say.

1:12:32David Whiteman PhD: Yeah, I think Jen and Michelle Wong have it covered with sunscreen and all the misinformation around it being an endocrine disruptor or it causing skin cancer. I just hope that dermatologists, skin influencers, and if they listen to the podcast, kind of moderate some of the extremist views that they may have in either direction around everyone needs to get out in the sun, or if you're out there in the sun, you're like threatening your life and you should, you know, go to the beach or should never go to the beach. Or if you're, you know, outside going to the grocery store, like you should be covered head to toe and drive with long sleeves, or you're somehow not a responsible, you know, person.

1:13:23David Whiteman PhD: You know, because some of these things can also be damaging because they can leave patients feeling like they're the reason why they developed the cancer or they're the reason why their health has been harmed. I've seen this consistently for survivors that are vulnerable enough to put their stories up there and stopping melanoma and other skin cancers. The bullying that happens with people telling them that it is your fault, that kind of moralistic kind of way of messaging, I think on social media, sometimes does a disservice to survivors.

1:13:56Ade Adamson MD: My final question is, do you have any final take-ems that you'd like to leave with my audience? And or are there any messages that you haven't had a chance to get out there or weren't addressed in this conversation that you want to insert now? David, would you like to start? Well, I would say skin cancer remains a public health problem in many parts of the world, Australia, New Zealand, US, many people develop skin cancer. Skin cancers are largely preventable, not 100%, but largely preventable. And we can prevent them through reducing our exposure to the sun. And I think that message should be heard.

1:14:36Ade Adamson MD: And then people can make decisions about how they do that in their own way. And if you see changes on your skin, spots, lesions that are changing, do get them seen because it could be a skin cancer and it could be something that could kill you. So don't leave it.

1:14:54David Whiteman PhD: I think the discussion around skin cancer prevention is really nuanced and that people should lean into that nuance and really kind of listen to people that are offering data, whether that is through studies, sound rational arguments, guidelines, and really thinking critically around, just like David brought up, you know, a little bit of something is okay, but a lot of something in either direction, i.e. no sun exposure or too much sun exposure is bad. You know, we need to live somewhere in the middle and we don't need to be so afraid of the sun that we don't do things like go to the beach, have a picnic outside, exercise, all things that are beneficial to the human condition and health in general.

1:15:55David Whiteman PhD: And this focus on this one specific type of cancer shouldn't crowd out every other aspect of your life, even if you're a survivor.

1:16:09Ade Adamson MD: Thanks again to David and Aday for agreeing to this roundtable. I hope that was as informative for you as it was for me. Quick reminder, if you're not already subscribed to the podcast, please do. And if you haven't already, please give the podcast a review. If you enjoyed this podcast episode, please share. And if it's accessible, you can also support the podcast on Patreon at patreon.com slash the eco L. Thank you again to all my Patreon supporters who have supported my science communication efforts over the years. That's all for this week. Thanks for tuning in.