Melanoma: Understanding This Serious Form of Skin Cancer

What is melanoma?

Melanoma it is a malignant tumor that derives from the cells that give the skin its color: melanocytes. It is a potentially serious cancer if it is not diagnosed and treated in the early stages, so early diagnosis is extremely important.

The incidence of melanoma has increased enormously in the last 50 years, in parallel with recreational sun exposure and the habit of tanning, especially in countries with high solar radiation and a population with fair skin.

How is it produced?

The mechanisms of cancer production are complex, and include many factors, both genetic and environmental. In the case of melanoma, sunlight is the main factor responsible, especially in people with white skin and blue eyes, with numerous freckles or nevi, and with a family history of melanoma.

It has been shown that the sun exposure that implies the greatest risk is constituted by burns or intense and punctual sun exposures during the first years of life, that is, recreational or vacation sun exposure. Indiscriminate exposure to UVA rays should also be considered a risk factor.

Symptoms

In most cases, melanoma begins as a freckle or nevus, but it usually shows different characteristics from the freckles that all people have. It is a freckle of little symmetrical shape, not round, with irregular or poorly defined edges, with various colors inside (especially if one of them is very black), and in general it tends to quickly reach a larger size than the other freckles ( more than 6 mm - the size of a pencil eraser).

Melanoma can appear on normal skin, or arise from a pre-existing freckle or nevus. For this reason, in people at risk it is as important to control suspicious freckles as

Diagnosis

It is very important that a suspicious freckle is evaluated by a dermatologist. In general, the diagnosis of melanoma is made on clinical suspicion after direct vision and confirmed by biopsy.

A biopsy consists of the excision of the lesion and its microscopic study. Studies show that the dermatologist has a markedly greater ability than the general practitioner and other specialists to recognize melanoma. It is important to go or be referred to a dermatologist if melanoma is suspected. The insurances have a wide medical team of specialists in Dermatology.

The skin biopsy confirms the diagnostic impression of melanoma and also assesses several parameters important for prognosis and evolution.

The most important is the thickness of the melanoma, that is, the depth to which the malignant melanocytes reach in the dermis. If this thickness or depth (known as the Breslow level) exceeds 1 mm, the melanoma has a higher risk of having spread to distant sites (metastasis).

If the melanoma meets certain criteria and is considered a risk of metastasis, staging should be performed using the sentinel node technique. In this procedure, which does not usually require hospital admission, a tracer is injected that identifies the first lymph node to which the area where the melanoma is located drains.

This node is removed and analyzed, and it is looked for if there are metastases in it, that is, if the melanoma cells have invaded it. The result of this test directs and indicates further treatment.

Treatment

The initial treatment is always melanoma surgery, that is, removal. This procedure can practically always be performed under local anesthesia. The margins of melanoma excision, that is, the area of ​​healthy skin that is excised around it, must be adequate to the thickness or Breslow level that is observed with the biopsy analysis.

This means that in many cases, when the Breslow level is known through the first biopsy, a second intervention is necessary to widen the margins (in many cases, this re-enlargement can be done in the same operative act as the sentinel node biopsy).

Regarding subsequent treatment, in many low thickness melanomas (Breslow less than 1 mm) neither should be performed. In melanomas with a high risk of metastasis (thick melanomas and positive sentinel node biopsy), the behavior varies according to each patient and according to the centers.

The efficacy of chemotherapy and immunomodulatory treatments (vaccines) used to date has been very limited. The only drug approved for the treatment of high-risk melanoma is interferon. If there are metastases, life expectancy is significantly reduced, and the treatment to be considered may be surgical (removal of metastases) depending on each patient and their location.

Precautionary measures

Early diagnosis is very important in a cancer in which the efficacy of the treatments is very limited when there has been invasion and extension of the disease. Campaigns aimed at the general population warn about indiscriminate exposure to the sun, especially in people with fair skin, with many freckles, or with a family history of melanoma.

Sunbathing should be avoided in the central hours of the day, and sunscreen lotions or lotions should be used correctly. Photoprotection is especially important in childhood. The effectiveness of sunscreens, even those with a high protection factor, is limited, so physical protection should also be used with wide-brimmed hats, caps or shirts made of suitable fabrics that do not let light through.

This is especially important in the summer season, in the hours of greatest sunshine, in places such as the beach where the reflection of light on the sea and the sand increases irradiation, and at high altitudes (high mountains) where the filtering of light because of the atmosphere is less.

Likewise, everyone should learn to look for new freckles, different from the others, and that meet the ABCD rule of asymmetry, uneven edges, different colors and diameter of more than 6 mm. At the slightest suspicion of melanoma, the patient should be seen by a dermatologist.