melanoma | Melanoma (Skin tumor)

Melanoma
(Skin tumor)




Description
Melanoma is the most serious form of skin cancer. In Canada, the number of people diagnosed with melanoma is estimated at 6800 each year and more than 1000 of them will die.

It is important to know that melanoma has very serious consequences only if it is not diagnosed. It is fairly easy to recognize and very easy to treat if it is detected in time.

Here are some of the risk factors that predispose to melanoma:
Excessive exposure to sunlight and ultraviolet (UV) rays;
A history of blister-forming burns (especially in childhood);
The presence of atypical moles;
The presence of moles in large numbers (over 50);
Pale complexion (mostly for those with blond or red hair with green, blue or grey eyes);
Freckles or sunburn-sensitive skin;
A personal or family history of skin cancer
Weakened immune system
Taking medications that increase skin sensitivity to UV rays;
A history of childhood cancer for the treatment of which radiation and immunosuppression (less frequently) were used.
Causes
The cancer is caused by a mutation of DNA (genetic material) in the nucleus of a cell. After having undergone a mutation, the genes lead to the continuous division of the cells, which produces an anarchic growth of cells with the same mutation. The process is not fully understood, but researchers are aware of a large number of carcinogens, that is, substances that cause cancer or increase the risk of the onset of this disease.

In the case of skin cancer, the main carcinogen is actually sunlight. Studies have shown that melanomas are more common in people who have spent a lot of time in the sun. Damage caused by ultraviolet (UV) rays can cause mutations. The incidence of melanoma is increasing, reflecting the increase in sunbathing in the population since the Second World War.

People of African descent are less likely to present melanomas than white ones, even though they may be suffering from a rare form that appears on the mucous membranes, for example inside the mouth. In white people, those with paler skin are more prone to this condition. The risks are also more important for those with blue or green eyes, pale hair and freckles.

The most important sun exposure usually occurs during childhood, and people who have had severe sunburn before the age of 18 are exposed to increased risk of skin cancer. In addition, UV rays emitted by the sun or a solar lamp and X-rays have been associated with the risk of melanoma, as well as exposures to radium or arsenic.

The skin cells called melanocytes produce the brown pigments that appear when the skin is tanned by the sun. Melanomas always appear in the melanocytes. They can appear in the moles present on the skin, which are in fact clusters of melanocytes, or in melanocytes isolated in the normal skin.

Some moles present increased risk. Dysplastic naevi are abnormal moles and can later give birth to melanoma. The way to recognize them is very simple. They present at least one of the following characteristics ("ABCDE"):

Asymmetry – the mole is not round as usual, but has a strange or elongated shape.

Border – The border is irregular, like a rough shoreline on a map, and its edges gradually disappear into the skin rather than form a neat line.

Colour – the mole has regions whose colour varies and can be white, blue, red or (more particularly) black.

Diameter – the diameter is greater than the eraser of a pencil (or greater than 6 mm).

Evolution – it changes colour, shape, surface and its symptoms are variable (e.g. bleeding, itching, crust formation).

Symptoms and Complications

Melanomas are a visible form of cancer, unlike other forms that appear inside the body (e.g. breast or prostate cancer). Melanomas usually cause visible and overt changes. It is important to recognize the signs and have the doctor check for the suspicious moles.

A mole that is transformed is not necessarily cancerous, but it is important to have it examined. The appearance of a new mole on the skin is also important. It is important to consult a dermatologist or family physician when the following transformations occur:

The margin of a mole becomes rough or less well defined, or its pigmentation (coloration) extends into the surrounding skin;

A mole grows, takes a new coloration, rises from the skin or presents blisters or irregularities;

A mole becomes hard, is covered with a crust or has irritation or bleeding;

Ulceration or cut does not heal after one month;

Black spots appear under the base of the fingernails;

An outgrowth or an abnormal color stain appears on the skin.

A melanoma that is not treated is a very dangerous skin cancer as it can spread to other parts of the body and can even be deadly.

Diagnosis

Your family doctor or a dermatologist can diagnose melanoma. A sample of the suspect tissue is taken from the mole (biopsy). It is examined in the laboratory to allow screening of cancer cells. A biopsy of the surrounding lymph nodes or other tissues can be performed to determine if the cancer has spread.

Treatment and prevention

If melanoma is detected and eliminated quickly, before it penetrates under the skin, the chances of healing are close to 100%.

If the melanoma has spread horizontally (on the surface of the skin), the prognosis remains very favorable as it has not penetrated deep under the skin. There are various types of melanoma, but in itself the type is less important for the prognosis than its thickness and depth of penetration.

The treatment of melanoma uses surgery that removes the lesion as soon as possible. In the early stages, surgery can be very simple and painlessly, much like extracting a wart. If the cancer has spread in the skin, surgery can leave a mark. Even the relatively deep melanomas can be cured if they have not reached other organs.

Chemotherapy, radiotherapy or immunotherapy may be recommended, depending on the severity and degree of melanoma diagnosed.

To prevent melanoma, it is important to avoid excessive exposure to sunlight. Sunburn is more serious, but even excessive tanning greatly increases the risk of melanoma. It is important to always use sunscreen (with a sun protection factor or SPF of 15 or more) in sunny weather, and to reapply it as often as recommended. If possible, the sun should be avoided when the ultraviolet rays are at their maximum intensity (between 10 a.m. and 4 p.m.). In addition it is necessary to wear clothes, which protect effectively against the rays of the sun. This includes covering the arms and legs and wearing a wide-brimmed hat. Similarly, it is recommended to always wear sunglasses that offer protection against both UVA and UVB rays. As UV rays can cross the clouds, vigilance must be exercised even when the weather is overcast. Another recommendation that applies to everyone: avoid tanning beds because they increase the risk of melanoma.

It is also important to protect children from the sun. Children often have tanned skin in summer, and their parents assume that as long as they do not sunburn, there is no danger. However, children's skin is always more vulnerable, and tanning increases the risk of skin cancer appearing later.

Since it is important that melanoma is detected as soon as possible, everyone should perform a regular skin examination with special attention to any new or changed moles or skin lesions. If you notice anything suspicious, make an appointment with your doctor without waiting to get the advice of a specialist.