Skin cancer: types, causes, symptoms and prevention

Skin cancer is one of the most common cancers in the world and usually develops in areas of the skin exposed to solar radiation.

Each year more than 1 million new cases of skin cancer are declared in the world , making it one of the most common types of cancer.

Although most of them are not fatal if detected and treated early, it is important to know their nature and the best ways to prevent it.

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It must be taken into account that, although it is the most common, skin cancer does not always develop in areas exposed to solar radiation. There are different types of skin cancer and different risk factors that can lead to its appearance.

Therefore, in today’s article we will see the most common types of skin cancer, specifying both their causes and symptoms, as well as the associated risk factors and the best strategies to prevent their development.

What is skin cancer?

Like any type of cancer, it consists of an abnormal and uncontrolled growth of the cells of our own body, which, due to a mutation or damage to their genetic material, lose the regulatory system of their reproduction.

This causes them to grow more than they should and end up causing the formation of a tumor, which can be malignant and receive the category of cancer.

Therefore, skin cancer is the type of cancer that develops in the cells of the epidermis . Although it usually appears in the areas most exposed to the sun, it can also appear in regions of the skin that never come in contact (or very little) with solar radiation.

Although, as we will see, the characteristics depend on the type of skin cancer suffered, usually all are characterized by the appearance of lumps, lesions or ulcers in the affected region.

However, most skin cancers can be treated with surgery if detected quickly, since they are usually located on the surface and do not spread to other organs.


Skin cancer develops when skin cells undergo mutations in their genetic material , which cause them to grow uncontrollably and lead to cancer. All these errors in genes occur spontaneously, although there are certain factors that increase the probability that they arise, as there are compounds that damage the genetic material of cells.

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One of them is ultraviolet radiation, which is present in sunlight. Therefore, the main cause of skin cancer development is prolonged exposure to solar radiation, which causes skin cells to slowly damage until cancer can develop.

However, there are some skin cancers that appear in regions of the body that are practically never exposed to sunlight, in which case the causes are not too clear.

In addition, there are some risk factors that predispose to developing this type of cancer: having fair skin, having moles, having suffered sunburn as a youngster, living in very sunny climates and / or high altitudes, having a weakened immune system, being exposed to toxic substances such as arsenic, family history …

Where does it appear?

Skin cancer is one that develops in the epidermis, which is the most superficial layer of the skin . It is the layer that suffers the impact of solar radiation, which explains why it is in it where skin cancers arise.

We know that in this epidermis there are three main types of cells. Depending on which of them is affected by the mutation, we will be facing one type or another of skin cancer. The three cell types are as follows:

1. Melanocytes

Melanocytes are the skin cells responsible for producing melanin , a pigment that, in addition to giving the skin its color, serves as a natural protection against solar radiation. These melanocytes are found in the lower part of the epidermis and increase their functionality the more we expose ourselves to the sun. This explains that when we sunbathe we get brown, as these cells produce more melanin to protect us from it.

2. Basal cells

Basal cells are those that are found, as their name suggests, at the base of the epidermis. They are found just below the squamous cells and their main function is to produce new epithelial cells .

3. Squamous cells

Squamous cells are those that are found in the uppermost part of the epidermis, that is, they are those that are in contact with the outside. They are the cells most exposed to solar radiation and, therefore, the most easily damaged, undergo mutations and lead to tumors.

The 3 main types of skin cancer (and their symptoms)

There are many different types of skin cancer, as there are some that affect the blood vessels of the skin, others in the sebaceous glands, in the hair-producing cells, etc. Anyway, we present the three main types of skin cancer, which are determined by the type of cell affected .

As we will see, the most aggressive type of cancer is that which arises in melanocytes. Fortunately, being in more internal regions of the skin, it is not the most common. The most common are those that occur in basal or squamous cells.

1. Non-melanoma skin cancer

For ease of classification, skin cancers that do not occur in melanocytes are grouped into a single group . In it, we have both those that develop in basal cells and those that develop in squamous cells.

Non-melanoma types are the most common among skin cancers, since approximately 75% of the skin cancers that are diagnosed are from this group. 1 million new cases are detected every year in the world.

1.1. Basal cell carcinoma

Basal cell carcinoma is a type of skin cancer that, as its name suggests, appears in the basal cells of the epidermis. It usually develops in the areas of the skin most exposed to the sun, especially the head and neck, although it can sometimes appear in regions that do not suffer from the incidence of ultraviolet radiation, such as the genitals.

Basal cell carcinomas are recognized because a sore that does not heal is often seen and it comes up without explanation. These injuries usually have one of the following characteristics:

  • Appearance of translucent lumps with visible blood vessels.
  • Appearance of lesions similar to a white scar.
  • Formation of scaly and reddish patches.
  • Appearance of brown, black or blue lesions.

However, basal cell carcinoma rarely brings serious complications, as it is very rare for it to spread to other organs. However, the possibility of increasing the risk of developing other more serious types of cancer is being studied. Therefore, it is important to treat it early. Removal surgery is usually sufficient.

1.2. Squamous cell carcinoma

Squamous cell carcinoma, also known as squamous cell carcinoma of the skin or squamous cell carcinoma, is the most common type of skin cancer since it is the one that develops in the outermost layers of the epidermis, which are the ones that receive the most amount of ultraviolet radiation.

Basal cell carcinoma develops most frequently in areas most exposed to sunlight, such as the hands, lips, ears, nose, etc., although it can appear in other parts such as the feet, genitals and even inside the mouth.

The characteristics of the lesions depend on the place where they appear, but are usually the following:

  • Formation of sores with scaly crusts.
  • Appearance of a firm red lump.
  • Formation of wart-like patches.

Although rare, squamous cell carcinoma can spread to other organs, especially the lymph nodes, in which case it can be fatal. Hence the importance of detecting it quickly and treating it early. Surgery is usually enough to treat the cancer.

2. Melanoma

Melanoma is the most aggressive type of skin cancer , although it is also the least frequent, but this does not mean that it should be underestimated, as more than 280,000 cases continue to appear each year in the world.

Melanoma can appear anywhere on the body. And, although it is true that it tends to do so in the parts exposed to the sun (back, hands, legs, arms, nose, ears, lips …), it can develop in areas that do not suffer from the incidence of sunlight, even in the intestines . The exact causes of many melanomas are not yet known.

The main symptom is that new moles appear on the skin or that existing ones change in size or shape. However, one of its main problems is that it does not always result in the formation of a mole, since as the melanocytes are in more internal layers, they often do not show any manifestation on the skin.

If caught quickly, a melanoma can be treated with removal surgery. However, as sometimes it does not show symptoms until it has spread to other organs (hence it is the most serious form of skin cancer), treatment may need to include chemotherapy or radiation therapy.


While it is true that some cases of skin cancer are of unknown cause, virtually all are due to prolonged exposure to solar radiation. Therefore, the best form of prevention is to limit the time you spend in the sun, in addition to always using sunscreen when you are going to be exposed to it.

We must always check our skin and, before the appearance of any mole, sore or lesion whose origin we do not know, it is important to go quickly to the doctor. Early detection greatly increases the chances that treatment will be successful.


by Abdullah Sam
I’m a teacher, researcher and writer. I write about study subjects to improve the learning of college and university students. I write top Quality study notes Mostly, Tech, Games, Education, And Solutions/Tips and Tricks. I am a person who helps students to acquire knowledge, competence or virtue.

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