Melanoma: There's no such thing as a healthy tan

In November 2023, a meeting on malignant melanoma, entitled "Challenging Malignant Melanoma", was held at the Champalimaud Foundation. It was organised by the Dermatology Unit and aimed at doctors and researchers from various specialisations. The organisers consider it a success and intend to repeat this type of event to bring together clinical and scientific expertise.

Malignant melanoma, the most lethal of skin cancers, is on the rise in every country in the world except Australia (the country that has invested the most in its prevention over the last 50 years). In the United States, the number of deaths from melanoma has remained stable due to the development of new therapies in recent years.

This is what dermatologist Claus Garbe, who studies the epidemiology of skin cancers at the University of Tubingen, explained at the opening of the meeting held last November at the Champalimaud Foundation. The bad guy? Exposure of the skin to ultraviolet rays. "Sunbathing isn't healthy and sun cream doesn't help," he said.

Daniela Cunha and Miguel Correia, from the Foundation's Dermatology Unit, who were behind the organisation of the conference, talk here about some of the key points of the event, particularly with regard to the future of artificial intelligence in the early diagnosis of melanoma and the new molecular therapies that are emerging for its treatment.

But they also stress the importance of collaborating with family doctors in the early diagnosis of melanoma, the potential influence of these professionals in changing harmful behaviours and the role that the recently reformulated Dermatology Unit will play as a "promoter of high-quality medical education in the area of skin cancer" (in Miguel Correia's words).

What was most relevant about the meeting on melanoma that took place recently at the Champalimaud Foundation?

[Daniela Cunha]

Above all, the fact that the approach to the subject was neither strictly clinical nor strictly scientific, but rather very translational and transversal, and very focused on innovation in the clinic, in therapy and in melanoma research. 

What was really different was that we brought together, on the same stage, experts in early diagnosis and screening, and some of the leading specialists in the most innovative research in terms of non-invasive diagnosis and immuno-oncology (the state-of-the-art in terms of oncological treatment).

It was this perspective of merging clinical practice and research that we wanted to give to the event, because, for patients, the benefit is greater when we have the best of clinical practice hand in hand with the best of research.

What were the highlights of the meeting?

[Daniela Cunha]

One of the hot topics was the role of artificial intelligence [AI]. We are moving towards a medicine that, in my view, will be increasingly supported by AI. That's why we must know how to use it with good clinical judgement, for the patients’ benefit. 

One of the speakers in this area was Josep Malvehy, director of the dermatology unit at the Clinical Hospital of Barcelona, an expert in non-invasive diagnostics. Malvehy spoke about AI-assisted diagnostic devices — some of which are already in use, others still in the experimental phase — but not without pointing out some of the weaknesses of AI when applied directly to the clinic.

This is a very hot subject that needs to be discussed seriously, without scepticism or dogma. And he gave a very mature analysis, from someone who has been working on this for a long time and has a lot of experience. 

Another important speaker was Markus Maeurer — leader of the Champalimaud Foundation's Immunotherapy/Immunosurgery Group — who discussed future therapeutic approaches in the field of vaccines and cell therapy in the specific case of melanoma. And Bruno Silva Santos, group leader and deputy director of the Institute of Molecular Medicine (IMM) in Lisbon, who spoke about the main avenues of research into immunology and cancer and immunotherapy, a treatment in which melanoma has, shall we say, played a pioneering role in terms of clinical application. 

When I started my training, metastasised melanoma was a death sentence — and it's fascinating to see the changes in the treatment of melanoma, which have also taken place for other tumours. Immunotherapy is now playing an increasingly important role, not only in melanoma and skin cancers, but also for other types of cancer.

[Miguel Correia]

As [Daniela] said, I think this meeting’s fusion between basic science and clinical practice was a striking and differentiating characteristic in relation to other scientific meetings. Above all, it showed the Champalimaud Foundation's Dermatology Unit as a promoter of high-quality medical education in the field of skin cancer.

This second aspect strikes me as innovative and will be pursued. What I mean by this is that the symposium was not an isolated event, but part of a sequence of events that marks the position of the Champalimaud Foundation's dermatology service in medical education at all levels, from general and family medicine to the most specialised Cutaneous Oncology specialists.

AI was therefore a prominent theme. But can an algorithm be better than an experienced clinician at recognising and diagnosing melanoma from images?

[Daniela Cunha]

Comparative "doctor versus machine" studies have already been carried out for images of specific lesions. And it has been concluded that, for the most typical lesions, the machine does better than the human eye. But it does not when it comes to dubious and rarer lesions, such as amelanotic melanomas, which can appear as pink papules. These are atypical melanomas, because melanoma typically is a black lesion. And in atypical lesions such as these, machines haven’t yet surpassed the human eye.  

I see AI in dermatology as a partner. I don't think we're going to be replaced by machines. AI is something that's very important to develop because it's a great diagnostic aid. But patients are not just images of their tumours. When we assess a patient, we palpate their skin. We touch the skin to see whether or not it's rough, we feel its texture, we press on the skin to see if the tumour is more or less infiltrated. At the moment, no machine can do this.

Even if we one day have robots capable of making tactile assessments, I don't think AI will replace us in the interaction we need to have with patients. A patient, particularly in the oncology field, is a vulnerable person and human interaction is crucial for managing expectations, stabilising anxiety about the diagnosis, and in the personalised way we approach each case.
 
I believe that artificial intelligence will become a very important diagnostic and therapeutic weapon in the near future, a tool that we should have by our side and cherish. In fact, we are all already using artificial intelligence in our daily lives without realising it. Personally, I don't feel threatened and I believe that the greatest benefit for patients will come from AI working with doctors and not against them.

As has already been mentioned, the symposium was also about immunotherapy, cell therapy and vaccines against melanoma. Could there be vaccines for treating melanoma in the future?

[Miguel Correia]

Researchers have been working for many years on the specific issue of vaccines [not preventive, but therapeutic] against melanoma – and the initial results were less than exciting. By using messenger RNA technology [mRNA, the technology used for COVID vaccines], we could get there. As to Immunotherapy, it is indeed a solid, proven progress. Cell therapy also has a lot of potential. 

[Daniela Cunha]

The results of a clinical trial testing the combination of an mRNA vaccine with pembrolizumab (one of the main drugs used in immunotherapy) were recently published. They are indeed exciting, but we are not yet at the stage of a therapeutic use outside clinical trials.

One of the aims of the symposium was to have a diversified audience, from family doctors to bench scientists. The talk by Alexandra Seixal, from Via Verde Saúde Seixal, really addressed the role of family doctors in relation to melanoma. Why is their role so important?

[Daniela Cunha]

Concerning the audience, we indeed planned and managed to have this diversity and richness of backgrounds. As far as family doctors are concerned, since they are close to a very wide range of patients, each doctor has a very high potential for early diagnosis, prevention and monitoring of a huge number of patients. This is crucial.

What should family doctors know? They should recognise the most important warning signs for early diagnosis, such as altered lesions, the so-called "ugly duckling mole” sign. When a family doctor is examining a patient, he or she usually looks at the patient's back, who has come to the appointment because of a cough or some other reason. And among the various moles that the patient may have, the doctor has to be able to detect any mole that is different – because it is much darker, or because it is much larger, or even because it is lighter than all the others. That’s the ugly duckling mole among the whole litter of ducklings. It's important to recognise the "ugly duckling".

General practitioners and family doctors are a source of early detection because we know that melanoma screening initiatives are not enough – and this doesn't just apply to dermatology. The fact is that, in general, the people who get screened are those who are naturally more alert and who would go to the doctor earlier because of a mole on their skin. 

That's why one of the major roles of the general practitioner and family doctor is to identify patients who probably wouldn't get screened because they're not aware of the risk of melanoma – but who, because they have another health problem, go to their doctor and end up being observed.
 
What's more, family doctors can encourage their patients to look at their own skin. It's not possible to photograph the skin of the entire population, so it's important for each person to pay some attention to their own moles, to get a sense of whether they present any changes or if there are any new ones. In other words, teaching patients to look at their skin is also critical and it is also an important awareness-raising role family doctors have.

There are also measures for limiting exposure to solar radiation that family doctors can transmit to their patients, such as avoiding exposure to the sun at the riskiest times of the day, wearing protective clothing, hats, sunglasses, and obviously applying and reapplying sunscreen to exposed skin areas. Family doctors are therefore key to educating people about the prevention and early diagnosis of melanoma.

[Miguel Correia]

I'd like to add that the family doctor is the community doctor. Prevention behaviour in relation to skin cancer, particularly with regard to exposure to the sun, can only be modified at key moments. And the key moment in the life of a family or in the life of a community is when someone very close to them is diagnosed with skin cancer. In such cases, the family doctor is in the best place, as a health technician, to seize that moment and provide health education to the whole family and the surrounding community. That's why these doctors must be trained to do this. 

I believe that events such as this symposium, which are open to general practitioners and family doctors, provide these doctors with the academic training and motivation to help the communities they come into contact with modify their risky behaviours. So I think that the family doctor is fundamental to fighting skin cancer from the earliest stages.

Is the Portuguese population aware of these risks or are there still many people who aren't?

[Miguel Correia]

It depends on what the term "aware" means. If it means "knowing about it", I doubt there's a citizen in Portugal who isn’t. If it means changing their behaviour accordingly, that's a completely different story. 

Changing behaviours is very difficult. These are very deep-rooted cultural habits. This thing about going to the beach, playing ball without a T-shirt... As I've already said, changing this is only possible in times of crisis. And the family doctor can do this better than any prevention campaign. "Your sister had skin cancer, what was that like? It reminds me of the sunburns I caught… I'll tell my family what happened to Maria and tell them to be careful." That's how it works, that's how behaviour changes. And it's the family doctor who talks about Maria, João and Joaquim, not the prevention campaign on television. 

Do some people feel less susceptible to melanoma because they don't have fair skin, lots of freckles, light hair and eye-colour? Are these false beliefs?

[Daniela Cunha]

Melanoma is actually more frequent in people with lighter skin, light-coloured eyes, freckles; redheads are also much more susceptible to skin cancer and in particular to melanoma. A darker complexion means a lower risk, but the risk is still there! 

[Miguel Correia]

And there's another fundamental aspect that goes against this idea [of a non-existent risk]. It is that, regardless of skin colour, people today live many more years than they used to. And so, even if a person is dark-skinned and therefore less likely to get skin cancer at 50 or 60, they can still get it at 80 or 90. Today we see an explosion of skin cancers in dark-complexioned older people. Tanning is in fashion and people don’t decide whether or not to go to the beach based on medical advice. It’s much more irrational than that.

[Daniela Cunha]

There's a much more relevant reason for people going to the beach and exposing themselves to the sun despite the danger: in Western society, a person who is a little tanned is commonly considered to have a "nice colour" and to look healthy. But if your skin is pale, you look sick. This notion, which has become very much rooted in our society today, is completely wrong.

Another misconception that interferes with people's risk assessment, even though they know that the risk of skin cancer exists, is the idea that going to the beach is good for your bones. That the iodine at the beach is good for the bones; that children need to get the sea air and the sun’s rays to get more vitamin D. It’s true that vitamin D is synthesised in our skin as a result of exposure to UV radiation, but 15-20 minutes a day are enough and you don't need to get tanned or sunburnt to get this effect. And as vitamin D can also be obtained in other ways, including through food, you don't need excessive sun exposure, which increases the risk of developing skin cancer.

[Miguel Correia]

There's no such thing as a healthy tan. Tanning is a defence mechanism against UV electromagnetic radiation that has caused the body to try to defend itself. It's a defence mechanism for skin that has been attacked. I repeat: there is no such thing as a healthy tan.
 
At the same time, it's ironic that there's a giant cosmetics industry, which sells more than the drug industry, to correct changes in the appearance of the skin – the overwhelming majority of which are associated with exposure to the sun…

Miguel mentioned the importance of the Champalimaud Foundation functioning as a school of oncological dermatology. Has this always been an aim, or has the Dermatology Unit changed direction in recent times?

[Daniela Cunha]

Previously, the Dermatology Unit treated skin cancer cases, and also other skin diseases. But for the last year or so we've had a new team dedicated to diagnosing and treating skin cancer.

Organising events like this symposium on melanoma is part of one of the Dermatology Unit's fundamental principles, which is that of education in dermato-oncology.

Will symposia and conferences on dermatological oncology continue to take place as an integral part of the Unit's activity? 

[Miguel Correia]

Yes. There have been others before and there will be others after this one. Ours is a Unit of excellence in oncological dermatology and it also contributes to the medical community's knowledge of the subject. It doesn't keep the knowledge to itself, it helps spread that knowledge because it's in sharing that we all evolve. And this is a line that the Champalimaud Foundation's Dermatology Unit is clearly following. You can be sure that it will continue to do so.

Interview by Ana Gerschenfeld, Health & Science Writer of the Champalimaud Foundation.