Why does skin cancer occur?
The two main causes of skin cancer are, par excellence, genetic background and excessive exposure to UVA radiation (voluntary or for other reasons).
This does not mean that they are the only factors that cause cancer at the cutaneous level, that is, cancer is a chronic disease that can develop from genetic factors (abnormalities in cell replication) but environmental factors such as excessive UVA radiation also intervene, X or gamma rays.
What is the most common cause of skin cancer?
The most common cause of skin cancer is sun exposure. The type of sun exposure can condition one type or another of skin cancer.
If we focus on the most common environmental cause of the appearance of skin cancer, that is, solar radiation, we also differentiate some aspects between the two types of skin cancer. Although it is true that they share a clear derivation from excessive sun exposure and the action of UVA rays, but they have differences that define them.
While cases of non-melanoma skin cancer appear due to constant and continuous (daily) exposure to such radiation, for example, in the case of a person who works outdoors, such as bricklayers, rural people, sailors, etc. Usually the part of the skin affected is the one that has been constantly irradiated by the sun.
In contrast, melanoma cases are the consequence of intermittent or discontinuous, but at the same time, very intense sun exposure. Examples of these are people who go to sunbathe in the summer and can spend a whole day on the beach. Although the exposure time in this case is less than that of the previous case, we must bear in mind that it is much more intense and concentrated, compared to the previous one.
There is scientific evidence that shows that nonmelanoma skin cancer has developed due to burns due to excessive solar radiation, produced during childhood. Usually the part of the skin affected with this type of cancer is not the one that has been constantly irradiated by the sun, but rather the opposite, appears in areas that have not suffered such excessive solar irradiation.
Factors that can favor the appearance of skin cancer
There are other factors that can also predispose to skin cancer, or at least be a risk factor for it developing. Among these we have:
- Poor nutrition and an excessive intake of calories in food, especially in the childhood stage, can help and be the cause of the appearance of some cancers.
A poor diet (at any age) that generates nutritional deficiencies of fiber, vitamin A, vitamin C and vitamin E, and certain minerals, such as selenium, results in a decrease in the effectiveness of our immune system and therefore, of the resistance of our defenses.
The lack of nutrients that boost the immune system can be caused by an inadequate intake, by food intolerances and allergies that limit the intake of some foods, but also due to the deficiency of intake of some essential amino acids such as cysteine and methionine.
Diet (along with other forms of treatment) can help fight cancer, especially at the level of our body’s response and resistance to disease and minimizing the symptoms that are present. We must not forget that the treatments that are being most effective against cancer are those that are carried out jointly between various types of therapies and not through a single type. Addressing a problem from different angles is better than from a single perspective.
- Virus infections: Some viral infections, such as herpes,HIV,hepatitis B,human papilloma,are associated with the development of some types of cancer. Especially those that have skin lesions.
Main symptoms of skin cancer
Symptoms according to the type of exposure
Both types of non-melanoma skin cancer are the consequence of continuous solar radiation and mainly affect the areas exposed to the sun such as the skin of the face, followed by the ears, the backs of the hands, the shoulders and the arms. But in turn, there are differences between them, depending on how they manifest:
- Basal carcinomas, affect men and women equally, and are likely to appear more frequently after 40 years of age.
It manifests as a small skin disorder that persists for at least 21 days. At first it can be confused with an ulceration (small wound), with a rounded shape with little relief, which sinks in the center, without generating any type of crust. But when not treated, it increases in size, being able to exceed 6mm in diameter.
- Squamous carcinomas, usually appears around 50 years of age. It begins to manifest as a small bump or a small lump with a pronounced relief, the ulceration of which does generate a crust, but is free from itching.
Melanoma cases are the consequence of intermittent or discontinuous solar exposure, as well as very intense, which can be expressed in four different types:
- Malignant melanomas spread superficially, have little relief or nonexistent, but they are not symmetrical with defined edges and they are usually moles with several brownish colorations at the same time. They are the most common and widespread at any age and area of the body.
- Malignant melanomas called lentigines, appear after years of exposure to solar radiation, are large in size, brown in color, and have no relief. Therefore, they are more frequent in older people and appear in the areas where the sun has most commonly given us throughout our lives (face and arms).
There is also acral lentiginous melanoma, it is very rare and affects people with less predisposition (dark skin, dark eyes, dark hair, …), appearing on the mucosa and in areas of less pigmentation such as the palms of the hands or the soles of the feet, etc.
- Finally, there is also a type of melanoma called nodular (mayor may not have coloration). It is easy to distinguish due to its particular coloration, which includes shades from bluish-violet or reddish.
Symptoms according to the type of predisposition
In the most predisposed people are those with whiter skin, blonde or copper hair, lighter eyes and more freckles. Usually they appear lumps, protuberances, eczemas that are not eczema, ulcerations, strange spots, new freckles can grow or increase in size the existing ones.
When large freckles degenerate their shape, increase in size (greater than a lentil or more than about 6mm), change color (pink, blue, black, brown, …) and texture, it may be because they are transforming into a melanoma, so we should go to the specialist dermatologist as soon as possible.
In less predisposed people, they are those with darker skin, darker hair, dark eyes, few freckles and in their case they are very small. They are more commonly affected in areas of low pigmentation, such as the palms of the hands, the soles of the feet, the lips or other more sensitive mucosa.
Important note: That a person has a series of factors that predispose him more than another, to developing skin cancer, does not mean that he will develop it. Likewise, even if a person does not have such predisposing factors, it does not mean that they cannot get skin cancer.
More information on skin cancer
1 July, 2020