More than 100,000 new cases of skin cancer are counted each year in France. All must be taken seriously but melanomas, which represent about 4% of skin cancers, are the most formidable. They are responsible for about 1600 deaths a year in France.

But a regular examination of his skin can identify them before they commit too much damage. "90% of skin cancers detected in time can be cured," said Professor Thierry Passeron, a dermatologist at the University Hospital of Nice.

Carcinomas, often not very aggressive

Nine out of ten skin cancers result from the activation of epidermal cells that do not produce pigments, the keratinocytes. These carcinomas often occur after 50 years on uncovered areas of the body (face, neck, shoulders, back of the hands), insofar as they arise mainly from repeated overexposure to the sun. There are two types:

• basal cell carcinoma . Relatively mild, it is the most common (70% of skin cancers). It usually looks like a small brown pearl with dilated vessels. This lesion metastasizes infrequently, but it can gradually destroy surrounding tissues. It must be removed before it grows and generates an ugly scar.
• Squamous cell carcinoma (formerly called squamous cell carcinoma). It is less frequent (20% of cases) but more serious: it can spread from a distance and invade the lymph nodes. Better to extract the nodule quickly. Additional radiation therapy is sometimes necessary to prevent recurrence.

Melanoma, the most feared

Derived from the activation of melanocytes, the cutaneous cells that produce melanin, this aggressive tumor can occur in people of all ages anywhere on the body.

Its incidence has risen sharply for 30 years: 175% for women and 332% for men, according to data from the Public Health Agency France.

In two-thirds of cases, melanoma appears as a new pigmented spot that has not existed before. But it can also arise within a pre-existing mole.

Being the most serious skin cancer, it is better to diagnose it as early as possible. Otherwise it can generate metastases, spread quickly to the liver or brain, and become recalcitrant to treatment.

Self-diagnosis: a reflex to adopt

"Against skin cancer, prevention is essential," says Pr Passeron. You should regularly check your skin to check for any new suspicious spots, monitor your moles to make sure they are not subject to questionable changes (change in thickness, shape or pigmentation) and behave accordingly. reasonable vis-à-vis the sun, limiting indiscriminate exposures.

According to Harvard Medical School's American specialists, sunburns - especially during childhood and adolescence - increase the risk of melanoma by 80%. The use of tanning booths is also incriminated.