Melanoma is the most dangerous type of skin cancer. It is a malignant tumour that forms in melanocytes (cells that produce the pigment that gives skin its colour). 95% of melanomas occur in the skin and very rarely in mucous membranes, internal organs, etc.

Although as we age, the risk of developing skin cancer increases, it is one of the most common cancers in young adults (especially in women).

Over the last 30 years, it has increased exponentially. More than 150,000 cases are diagnosed in the world each year.

Preventing it and detecting it in its initial phase is essential, since when it is advanced it can even put life at risk.



The exact cause of melanoma is not completely clear, and it is most likely a combination of factors, with UV exposure being the most significant. Melanomas have also been associated to other risk factors:

  • Number of moles.- The presence of more than 50 moles throughout the body indicates a higher chance of developing melanoma than a person who has no or very few moles. Unusual (dysplastic nevus) moles are more dangerous, they usually have irregular edges, are larger and have several colours.
  • Age.- As we have mentioned, melanoma can appear at any age, and although more and more young adults are diagnosed, most melanomas occur before 55 years of age. From the age of 70, it is easier to find nodular or acral melanomas.
  • Sex.- It is slightly more frequent in women and usually appears on the upper and lower limbs of the body, because they have been more exposed to the sun. In general, melanoma in women usually has a better prognosis than in men.
  • Race.- Melanoma is more common in Caucasian individuals, since they have less pigmentation (melatonin) and are less protected from the sun. In people of colour, melanoma usually appears on the palms of the hands, soles of the feet and mucous membranes, because these are the areas where they have the least pigmentation.
  • Family history.- If a family member has had melanoma, you are more likely to develop it in the future. Although this may be due to a genetic mutation, it seems that it is most likely due to sharing a lifestyle.
  • Weak autoimmune system.- This means people with AIDS, people who are taking medication to prevent the rejection of transplants, etc.


Melanoma can occur anywhere on the skin, rarely in internal organs or the eyes.

Melanoma usually develops from a mole we already had and that alters its characteristics; these changes can be:

  • Size.- Careful with those over 6 mm
  • Irregular shape.- Normal moles tend to be circular.
  • Irregular edges. They may denote the appearance of melanoma.
  • Colour.- Careful with those that change colour or have several colours.


The only reliable way to diagnose melanoma is to biopsy the lesion on the skin, mucous membranes, etc. A pathologist will determine whether the sample is melanoma or not.


It is advisable that people at risk regularly examine their moles and, if they notice any significant variation, go to the dermatologist.

During this examination we can use mirrors to check our entire body, including the entire outline of our arms and legs, groin and even under the nails.



Treatment will be different depending on the stage of melanoma:

Treatment for initial phases.- Melanoma has not extended beyond the skin

It is completely removed, with a small safety margin of healthy skin. The process will require the intervention of a pathologist who will analyse whether the entire safety contour is clean or whether it is necessary to remove more.

It is advisable to biopsy the sentinel nodes.

Treatment for advanced phases. – Melanoma has spread beyond the skin

As in other cases of cancer, a medical committee will decide the following steps, in addition to removing the melanoma, which may include the following treatments:

  • Removing sentinel nodes.- If in doubt, the corresponding lymph node will be removed.
  • Targeted medication therapy: Trametinib, dabrafenib or vemurafenib may be used, for example, which will be more or less effective depending on the type of melanoma. Almost all treatments have significant side effects.
  • Immune system stimulation: With ipilimumab, interferon and interleukin-2, among others. Side effects are similar to flu symptoms.
  • Chemotherapy.- Generally administered intravenously, although it may also be administered orally.
  • Radiotherapy.- Directed both at the original melanoma and the affected lymph nodes.


Prevention is the best thing to do, as in most cases. And with this list of tips, it is easy to reduce the risk of skin cancer.

  • Avoid the sun at the times with the highest exposure (middle of the day).
  • Use sunscreen all year round.
  • Sunglasses.
  • Avoid tanning beds.
  • If you have many moles, check them once a year with a specialist (dermatologist). They will use a dermatoscope that draws a digital map. Your current mole map will be compared to previous ones to see if there are significant and suspicious variations.
  • Dermatology