5 severe sunburns before the age of 20 are enough to significantly increase the risk of developing skin cancer

All I can tell you about the sun is that it poses the same risk as wave (from what I know, huh, but if it can reassure you I'm not a scientist ;).

Anyway, if I had known that as a teenager, I certainly would have paid more attention. The thing is, I too have a lot of moles, and indeed I had repeated exposures when I was young. Finally, in the end, not sure that it changes anything, huh...

Update 12.08.2014 : Dr. Burzynski - The Cancer Plot

friendships

Atlantico: According to the results of a study published in Cancer Epidemiology, Biomakers and Prevention, the risk of developing melanoma is 80% in subjects who have had at least five sunburns before their 20s; that of developing basal cell carcinoma or squamous cell carcinoma is 68%. What is meant by sunburn? What intensity of sunburn are we talking about here?

Louis Dubertret: The sunburn is an inflammatory skin reaction, which occurs 12 hours after sun exposure, and more particularly to ultraviolet B rays of the sun. It is linked to the fact that after strong exposure to the sun, part of the skin cells are killed; it is the death of these cells that creates this inflammatory reaction which ends up causing the skin to peel a few days later.

The degrees of a sunburn can be very diverse : I have already had patients who had to be hospitalized in intensive care after a sunburn, while others only develop a small redness in the back for example. Therefore, in the study you mention, it is not possible, retrospectively, to determine the intensity of sunburn ; respondents could only recall the number of sunburns.

Sunburn is also a sign of intensive, and therefore reckless, exposure to the sun. To say that one has had more than five sunburns is equivalent to saying that the dose of UVB absorbed was very high during this period of life.

It would therefore be appropriate to rewrite the conclusion of the article more precisely, in the following way: people who have been shown, taking sunburn as an example, that they used the sun without precaution during their adolescence, have X% increased risk of developing skin cancer; in the study you refer to, sunburn was taken as a measure of the intensity of sun exposure.

How to explain this result? How does the nature of the skin, which is more fragile in children than in adults, favor the phenomenon?

In a general way, we are all very unequal in the face of the sun, as is also the case with tobacco, alcohol, etc. People with very fair skin are much more susceptible than others to sun damage, for example.

Other inequalities should be noted concerning the skin repair system put in place by each person after exposure to the sun.. The effectiveness of these systems is different from one individual to another, that is to say that two individuals who tan in the same way will not respond in the same way to the attacks of the sun.

And then finally, as your question raises, there is inequality in relation to age. The pigmentary system is not mature at birth; it reaches maturity around 22/23 years. Serious studies have been carried out in France, including one that consisted of counting the number of moles on the body of each school teenager in a village located in the South of France, and another in the North. It was then shown that the appearance of moles was very clearly linked to exposure to sunlight, which allowed them to conclude that the pigmentary system is not quite mature during adolescence. , that it is more fragile at this time. This increase in the number of moles in children exposed to the sun is no longer observed in individuals aged 30/40. It is common today to see, in adolescents aged 13/14 who have spent holidays in the sun without protecting themselves, the appearance of a multitude of moles two years later, without them having had any sunburns. This retarding effect is linked to a maturation, which we do not know on the molecular level, still incomplete of the pigmentary system.

What aggravating factors can be taken into account in the development of skin cancer?

Currently, the only environmental element really known to cause skin cancer is the sun.. There is nevertheless great discussions on the respective role of UVA and UVB : the latter are the most powerful, those which are stopped by glass and which are responsible for sunburn; UVA rays, on the other hand, are those that pass through the glass and do not cause sunburn.

Professor Caroline Robert, head of the cutaneous oncology department at Gustave Roussy, to show in a study that under normal living conditions, and in those where there is much more UVA in quantity than UVB, UVA contribute just as much as UVB to the formation of skin cancer.

Work is currently in progress on the dose rate; it is strongly believed that exposing yourself to sunlight for as long as possible, but without burning, is even more dangerous than getting a sunburn. The way of consuming the sun is therefore important: one of the messages today is to say that sunscreen products protect the skin very well provided you do not use them to stay longer in the sun.

Other factors include trigger factors. So, on skin already very damaged by the sun but which has not yet developed cancer, the occurrence of a wound accompanied by healing can promote the appearance of cancer. It is, for example, very common that on the skull of farmers who are heavily exposed to the sun as part of their activities, a wound can promote the appearance of skin cancer.

Regarding the lips, the lower lip is the most exposed to the sun, and is at greater risk of developing cancer than the upper lip. This risk is considerably increased in smokers because of the tar which is deposited on the lower lip..

On the other hand, there is no information to suggest that automobile pollution plays a role in skin cancer.

Are certain skin profiles more at risk of developing skin cancer?

We are all the more likely to develop skin cancer if we have fair skin.. The skin is like Benetton, all colors are represented: black skin has a pigment that does not contain sulfur, while red has a pigment that contains a lot. The more sulfur the skin pigment contains, i.e. the lighter it is, the more it is able to protect the skin but also aggravate sun damage.

Going back to the skin repair system after exposure to the sun that I mentioned above, we have the means to imagine the possibility of measuring, thanks to a machine in which a hair of the skin would be introduced, the ability of our system to repair damage caused by the sun.

Ways to fight against skin cancer exist when you are old. Some studies have shown that moisturizing very dry, permanently peeling skin reduces the frequency of occurrence of precancerous conditions. Moisturizing the skin is widely communicated advice to people starting to develop skin cancer.


Where is the boundary, in terms of risk, between high exposure to UV rays (which does not necessarily cause sunburn) and sunburn?

The border is above all individual, and even different according to the regions of the body.. The skin protects itself from the sun in two ways: firstly by tanning, which is a protection of modest quality, and by thickening of the epidermis, the main protection against UVB rays; the thicker it is, the more the damage linked to exposure to the sun is reduced. The thickness of the stratum corneum varies from one region of the body to another. This explains, for example, why the area behind the knee is one of the first affected by sunburn when walking in shorts in summer, because the skin in this area is thinner.

Some individuals have developed small watch-like devices that tell you the daily UV dose, although this is not adaptable to people's individual risk. Likewise, on the beaches, the UV radiation is indicated. So there are tools that exist to show people that the sun, although being a food for the skin, must be consumed in moderation.

With the summer holidays approaching, what practical advice can parents recommend regarding the exposure of their children?

The first message we delivered with the Cancer League years ago was: "protect the children". Indeed, the latter have no idea of the effects of the sun on their past.

To protect them, it is advisable to use sunscreen products, the application of which must be renewed regularly. Then, it is imperative toavoid exposure to the sun when it is at its zenith, that is to say between 12 p.m. and 16 p.m., a period during which the siesta allows you to rest, but also to avoid this exposure to the sun. We must also teach children to play under an umbrella, to wear a small hat, but also to put on sunglasses.. We always talk about the skin but it should not be forgotten that cataracts are linked to aging of the lens caused by light; eye protection is therefore very important as well.