What is melanoma?

Melanoma develops from cells in the skin called melanocytes. They usually look like a dark spot or unusual-looking mole on your skin. Early-stage melanomas (called thin melanomas) are usually cured with surgery.

Melanoma can start with a change in a mole or freckle you already have. Or you might notice a new, strange-looking mole, or a dark area of skin that was not there before. You can use the ABCDE checklist to help you if you think you may have a melanoma.

Some causes and risk factors are:

  • exposure to UV light, including sunlight, sunbeds and sunburn
  • having lots of moles or having strange-looking moles, including birthmarks
  • having a particular skin type
  • having close relatives with melanoma
  • having reduced immunity.

If you are worried about a mole, make an appointment to see your GP straight away. They can talk to you about your symptoms. If they think cancer could be causing them, they will give you further tests or send you to a specialist.

How melanoma develops

This section is for teenagers and young adults. It is about a type of skin cancer called melanoma. If you are looking for information about melanoma in people of all ages, you can read our general information about melanoma.

Melanoma develops from cells in the skin called melanocytes. The cells start to grow and divide more quickly than usual. In melanoma, the melanocytes start to spread into the layers of skin. When they grow out of control, they usually look like a dark spot or unusual-looking mole on your skin.

It is important to know the symptoms of melanoma, so it can be found and treated as early as possible. Early-stage melanomas (called thin melanomas) are usually cured with surgery.

When I was brushing my hair, I felt a mole behind my ear that was never there before. My brother and sister suggested I go see my doctor, because it was quite big considering it was new.

Jamie


Symptoms of melanoma

Melanoma can start with a change in a mole or freckle you already have. Or you might notice a new, strange-looking mole, or a dark area of skin that was not there before.

It can be difficult to tell the difference between a melanoma and a normal mole. You can use the ABCDE checklist to help you:

  • Asymmetry – Normal moles are usually evenly shaped all around. Melanomas usually have an irregular or uneven shape.
  • Border – Normal moles usually have a smooth-looking edge. Melanomas usually have jagged edges.
  • Colour – Normal moles are usually one shade of brown. Melanomas can have different shades of brown mixed with black, red, pink, white or even a blue tint.
  • Diameter – Normal moles are not usually bigger than the blunt end of a pencil. This is about 6mm across from one side of the mole to the other. Melanomas often grow bigger than this.
  • Evolving – Changes to a mole could be a sign of melanoma, so look for changes in size, shape or colour.
A diagram showing the possible changes to moles that you should look out for
A diagram showing the possible changes to moles that you should look out for

View a large version

Read a description of this image


See your doctor straight away if you have:

  • any of the ABCDE signs
  • any unusual marks on your skin that last more than a few weeks
  • tingling or itching in a mole
  • a crusting or bleeding mole
  • something growing under a nail, or a new, dark-coloured stripe along part of the nail.

If you are worried about a mole, make an appointment to see your GP straight away. Remember, melanoma can be cured when it is found early.

An image of a Macmillan Skin Cancer Nurse Specialist talking to a patient

Signs and symptoms of melanoma

Ruth Fox, Macmillan Skin Cancer Nurse Specialist, talks about the signs and symptoms of melanoma and how it is diagnosed.

About our cancer information videos

Signs and symptoms of melanoma

Ruth Fox, Macmillan Skin Cancer Nurse Specialist, talks about the signs and symptoms of melanoma and how it is diagnosed.

About our cancer information videos


Causes and risk factors of melanoma

Exposure to UV light

One of the main risk factors for melanoma is giving your skin too much exposure to UV light (radiation). UV light mainly comes from the sun and sunbeds. Too much UV light damages our skin cells and can cause melanoma years later.

If you want to look tanned, it is safest to use fake-tan instead of sunbathing and using sunbeds.

Sunlight

The number of people diagnosed with melanoma in the UK is increasing. People are going abroad on sunny holidays more often. But you can also get too much sun in the UK when the weather is hot. So you need to be careful in the UK, not just on holiday in hot countries. The risk from sunlight is higher for people with fair skin and pale or blue eyes.

Sunbeds

Using sunbeds increases your risk of getting a melanoma. Your risk gets higher:

  • the more you use them
  • the younger you are when you start.

You also get UV light from nail dryers during a gel manicure. The risk of melanoma is low, but to be safe it is best to air-dry your nails. You can also use sunscreen on the backs of your hands 15 to 20 minutes before the manicure.

Sunburn

If you get blistering from sunburn, especially as a child, it can increase your risk of getting melanoma later on. So it is important to protect the skin from sunburn, especially for children.

Having lots of moles or having strange-looking moles

Your risk of getting melanoma is increased by having:

  • lots of moles (over 100)
  • moles that are unusually big (over 5mm), with an irregular shape and colour.

This can run in families.

Having lots of moles does not mean you will get melanoma. But you should be careful about how much time you spend in the sun. It is also important to keep checking the moles. Your GP can send you to a skin clinic to learn how to do this properly.

Birth marks

Most birth marks do not increase your risk of getting melanoma. But having a birth mark called a congenital naevus can cause a higher risk. This is particularly if the birth mark is larger than 20cm across (from one side to the other). People with a congenital naevus should have regular skin checks at a skin clinic. It is a good idea to keep checking smaller birth marks for any changes. But they do not usually need regular check-ups by a doctor or specialist nurse.

Your skin type

You are more at risk of melanoma if you have:

  • fair skin
  • freckles
  • blue eyes
  • fair or red hair
  • a skin type that burns more easily.

You will need to be careful about how much time you spend in the sun, to stop yourself getting sunburnt.

If your skin is naturally darker (brown or black), your risk of melanoma is lower. This is because your skin is naturally more protected against it. But you can still get melanoma if you have darker skin.

Having close relatives with melanoma

Having one or more close relatives (parents, brothers, sisters or children) with melanoma increases your risk. The more relatives that have melanoma in the family (including aunts, uncles and grandparents), the higher the risk for you. This may be because you share the same skin type or your family members tend to have lots of moles. But occasionally, melanoma happens because there is a faulty gene in the family.

If one of your relatives has had melanoma, protecting yourself against the sun is even more important.

Reduced immunity

People with a weakened immune system are at a higher risk of getting melanoma. Your immune system fights infection and diseases in your body. It can become weaker after an organ transplant or if you have HIV.

If your risk of melanoma is higher because of your immune system, your GP can send you to a skin clinic. They will show you how to check your skin.


If you are worried about melanoma

If you think you have some of the symptoms of melanoma, you should go to your GP straight away. It is always best to get symptoms checked and you are not wasting your GP’s time. They will be able to talk to you about your symptoms. If they think cancer could be causing them, they will find out with tests or send you to a specialist.

Back to Melanoma

Having tests for melanoma

If you have symptoms, your GP will examine you and decide whether to refer you to a hospital specialist for further tests.

Treatment

Melanomas in young people are usually found early and cured. Surgery is the most common treatment for melanoma.

After treatment

Cancer can have a big impact on your life, even after you have finished treatment.