Melanoma: symptoms, causes and treatment

Melanoma is a malignant skin cancer that develops from pigment cells, also known as melanocytes. These cells are located in the deepest layer of your epidermis and produce melanin, the pigment that gives your skin its color. When these cells degenerate and grow uncontrollably, melanoma occurs.

Your skin consists of three layers: the epidermis, the dermis, and the subcutaneous connective tissue. Melanomas originate in the epidermis, but can grow into deeper layers and even spread to other organs via the blood or lymph system.

Melanoma is the fifth most common form of cancer in Belgium. In 2018, 3,489 people were told they had melanoma. The number of cases has increased in recent years, mainly due to frequent exposure to ultraviolet rays from the sun or tanning beds.

Basocellular carcinoma and squamous cell carcinoma are the most common skin cancers and account for approximately 9 out of 10 cases. These usually grow slowly and rarely seed. A melanoma, on the other hand, can behave aggressively and metastasize quickly. That is why it requires extra vigilance and rapid action.

Most melanomas occur on previously smooth skin. In about a third of the cases, melanoma develops from an existing mole. This means that you need to keep a close eye on both new spots and changes in existing moles.

The main cause of melanoma is exposure to ultraviolet rays. UV radiation damages the DNA in your skin cells. Normally, your body repairs this damage, but sometimes it goes wrong. If the damaged cell continues to divide, abnormalities can develop that ultimately lead to cancer. This process can take years, which explains why melanomas often only occur later in life.

Sunburn plays a crucial role, especially childhood sunburn. Children often spend a lot of time outside and their skin is more sensitive. Every time your skin burns so much that it blisters, your skin cells are damaged. This damage accumulates over the years and increases your risk of melanoma later in life.

Regular, prolonged exposure to the sun without burning also increases your risk. In people with a light skin type, who burn quickly and tan with difficulty, the risk is higher. Their skin produces less protective melanin and is therefore more vulnerable.

Tanning beds are an important risk factor that is often underestimated. The UV radiation from tanning beds is at least as harmful as that of the sun, sometimes even stronger. People who regularly use tanning beds, especially at a young age, are at significantly increased risk of melanoma.

Heredity also plays a role. If melanoma runs in your family, your risk is increased. This is because you can inherit a predisposition to sensitive skin or melanocytes that degenerate more quickly. It is also due to solar behavior within a family. If you have a lot of moles, or moles that look different, your risk is higher. These abnormal birthmarks themselves are not malignant but do indicate that you have an increased risk.

People with a weakened immune system also have a higher risk. This may be the case for people who have to take medicines that suppress the immune system after an organ transplant. This is because a well-functioning immune system plays a role in cleaning up cells that are beginning to degenerate.

A melanoma usually looks like an abnormal mole, but with features that distinguish it from ordinary moles. The ABCDE rule is a handy tool for recognizing suspicious spots.

A stands for asymmetry. Common birthmarks are usually fairly round or oval and symmetrical. In melanoma, the shape is often asymmetric and irregular. One half looks different than the other.

B stands for limitation. Normal birthmarks have a sharp, clear edge. In melanoma, the boundaries are often blurred and frayed. The edge may have outgrowths or gradually blend into the surrounding skin.

C stands for color, or color. Common birthmarks are usually one color: brown, dark brown, or sometimes pink. Melanoma often has multiple shades of color within one spot. For example, you see black, brown, red, blue or gray side by side. This variation in color is an important warning sign.

D stands for diameter. Melanomas are often larger than six millimeters, about the size of the eraser on the end of a pencil. Smaller spots can also be a melanoma, but size is a point of attention.

E stands for evolution or change. This is perhaps the most important signal. A mole that changes in size, shape, color, or thickness deserves attention. Even if a mole starts to itch, hurt, bleed without cause or release fluid, you should have this checked.

In addition to these ABCDE characteristics, melanoma can rise above your skin and often feel uneven or lumpy. It can bleed easily, for example if you accidentally scratch it. Small brown spots called satellite lesions may appear around the melanoma.

Melanomas can develop anywhere on your body. They usually occur on areas that are exposed to the sun, such as your face, neck, arms, and legs. In men, they often occur on the back; in women, they are relatively common on the legs.

The face is an important location in both sexes. Melanomas can occur here on the nose, cheeks, forehead, or ears. The hairy scalp is a tricky spot because melanomas are hard to notice here. They are hidden under your hair and you don't see them when you use mirrors every day.

Less common, but certainly possible, are melanomas under your nails. These look like a dark stripe under the nail that gradually widens. Melanomas can also develop on the palms and soles of your feet. In dark-skinned people, melanomas are relatively more common in these areas than in light-skinned people.

In rare cases, melanomas can also develop on mucous membranes, for example in your mouth, nose, or intestines. These melanomas are extra dangerous because they are often discovered late.

If you have a suspicious injury, everything starts with a thorough examination by your doctor. He or she examines the injury closely, often using a dermatoscope. This is a type of magnifying glass with a light source that helps your doctor better see the structure of the spot. Your doctor will pay attention to characteristics such as color, shape, surface, location, and size.

Your doctor also maps out your risk profile. He or she asks about your skin type, past sunburns, previous skin cancers in your family, and whether you're taking medications that affect your immune system. All of these factors help to estimate how likely it is that a suspicious injury is actually malignant.

When in doubt, your doctor may choose to photograph the injury and note the measurements. After six months, it will then be checked again to see if there have been any changes. If melanoma is strongly suspected, there is no waiting and removal will be carried out immediately.

The removal is done by means of a skin biopsy or an excision under local anaesthesia. This tissue is sent to the laboratory where it is examined under the microscope. This is the only way to determine with certainty whether there is a melanoma and how aggressive it is.

If the laboratory test shows that it is indeed a melanoma, a second procedure follows. This involves removing a wider area of skin around the melanoma site. In superficial melanoma, one centimeter is removed around the area; in the case of a larger and deeper melanoma, up to five centimeters. Removing this wide is necessary because there are sometimes already microscopic melanoma cells in the environment.

The nearest lymph node, the so-called sentinel lymph node, is also often removed. This is because melanomas often spread through the lymphatic system. By examining this gland, it can be determined whether the melanoma has already spread. If the gland contains malignant cells, more lymph nodes are often removed and a scan of your entire body follows.

Depending on the stage of melanoma, additional treatment may be necessary. In case of metastases, medication may be suggested that activates the immune system to attack cancer cells, or drugs that specifically target certain mutations in the cancer cells.

After successful treatment, good follow-up is essential. Melanoma can recur, either in the same place or elsewhere in your body. That's why regular checks come, usually every three, six or twelve months for a minimum of five years. Exactly how often depends on the size of the melanoma and whether lymph nodes were affected.

Self-treatment is absolutely out of the question. Some people try to remove suspicious areas themselves or treat them with creams or natural remedies. This is extremely dangerous. Melanoma can spread rapidly, and any delay in professional treatment reduces your chances of survival.

Vitamins and supplements are sometimes touted as prevention against skin cancer. While a healthy lifestyle is important for your overall health, there is no pill or supplement that offers reliable protection against melanoma. Do not rely on such means.

Ignoring suspicious spots in the hope that they will disappear on their own is perhaps the most dangerous pitfall. Melanoma doesn't go away on its own. On the contrary, it often gets worse as time goes by. If there is the slightest doubt about a mole, medical advice is necessary.

After successful treatment of melanoma, you can't sit back. The risk of a new melanoma remains increased, even after years of monitoring without problems. Lifelong vigilance and regular self-monitoring remain necessary.

‍How often should I check my skin?

It's a good idea to check your entire body every month for new or changing birthmarks. Choose a fixed time, for example the first day of each month. Use a large mirror and a hand mirror to see all sides. Don't forget areas like your scalp, between your toes, and under your nails. If you see anything suspicious, don't wait, contact your doctor right away.

Are tanning beds really that dangerous?

Yes, tanning beds are really dangerous for your skin. The UV radiation they emit is at least as harmful as that of the sun, sometimes even stronger. Regular use of tanning beds, especially at a young age, significantly increases your risk of melanoma. The World Health Organization classifies tanning beds in the same risk category as tobacco and asbestos.

Can melanoma also occur in young people?

Yes, although melanoma is more common in older people, it can also affect younger people. Many melanomas in young people are related to intensive sun exposure at a young age or the use of tanning beds. Sunburn in childhood increases the risk later in life. That's why good protection for children from the sun is so important.

What if melanoma runs in my family?

If there is melanoma in your family, you are at increased risk. Discuss this with your doctor. Regular check-ups by a dermatologist may be wise. You can't do anything about your genetic predisposition, but you can change your behavior: consistently protect against the sun, avoid tanning beds and, if in doubt, have your skin checked.

Is melanoma always fatal?

No, definitely not. The prognosis depends a lot on how early the melanoma is detected. SuperFICIAL melanomas that are removed in time have an excellent prognosis with a cure rate of more than 95 percent. The deeper and larger the melanoma is, the more serious the situation. This underlines the enormous importance of early detection.

Do I have to stay out of the sun all the time?

No, you don't have to stay completely out of the sun. Sunlight also has positive effects, such as the production of vitamin D. What matters is to use sunlight wisely. Avoid sunburn, seek shade during the bright afternoon sun, wear protective clothing and use plenty of sunscreen. Enjoy being outside, but do it wisely.

1. Skindr dermatologists
2. Health and Science: Skin Cancer (Melanoma)
3. eBPNet (Evidence-Based Practice Network)
4. Foundation Against Cancer: Melanoma
5. Euromelanoma Belgium
6. Huidkanker.nl: What is melanoma
7. Thuisarts.nl: Skin Cancer