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GB-PDO-01312 | Date of Preparation: November 2020

What is melanoma?

The information provided on this site is general education information and does not take the place of your healthcare professional’s advice. Please always follow your healthcare professional’s instructions and talk with him/her about any questions or problems you have regarding your health and treatment

Some people in the UK develop melanoma, a type of skin cancer.1 It is the 5th most common cancer in the country.2

Getting to know more about melanoma may help some patients feel more comfortable about their diagnosis and treatment. In this section you will find information about melanoma and the types of treatments available for advanced melanoma.

How does melanoma develop?

Melanoma often looks like moles; some develop from moles.1

About half of melanomas start in normal-looking skin.1

What causes melanoma?

Natural sunlight

Ultraviolet (UV) radiation is the main cause of melanoma

Sunbeds and sunlamps

Checking your moles

Keeping an eye on changes to your moles and skin is important for catching melanoma early.

You need to go to the doctor straightaway if you notice any of the following changes to a mole:1,4


The two halves of your mole do not look the same


The mole has irregular edges


The mole is not one solid colour but has multiple colours e.g. brown, tan, black, red


Getting larger


Changing shape, getting darker, becoming patchy or multi-shaded

Also be aware of other changes including: itching or pain, bleeding or becoming crusty or inflamed.

Cancer Research UK has a page with some photographs of abnormal moles and melanomas.

Advanced/metastatic melanoma

Metastatic means that a cancer has spread to other parts of the body. Treatments can usually be given to help shrink and control the new growths, called secondary cancers, and relieve symptoms.

To understand what metastatic melanoma means, let’s first have a look at how the stages of melanoma are determined.


This summary from Macmillan Cancer describes the stages of melanoma, which depends on how deeply the tumour has grown into the skin, and whether it has spread.

Stage 0

This melanoma is localised to the outermost layer of skin and has not advanced deeper. This non-invasive stage is also called melanoma in situ.

Stages 1 and 2

The melanoma is only in the skin and has not spread anywhere else in the body.

Stage 3

The melanoma has spread to the nearest lymph nodes or vessels, but not to anywhere else in the body.

Stage 4

The melanoma has spread to distant areas of skin or distant lymph nodes, or to other organs such as the lung, liver or brain. This is called advanced or metastatic melanoma.

Symptoms of advanced/metastatic melanoma7

Depending on which part(s) of the body the melanoma has spread to, the symptoms of advanced melanoma will vary from person to person.

All of the symptoms in the table can also be caused by other conditions. If you are worried about any symptoms, you should speak to your healthcare professional as soon as possible.

Part of the body Symptom(s)
Skin Hardened lumps in the skin
Lymph nodes Lymph nodes may feel hard and swollen, and may cause pain if they press on tissues or nerves nearby
Lungs Breathlessness, persistent coughing, pain in the chest or a collection of fluid around the lungs
Liver Swelling and discomfort in the right hand side of the tummy, under the lower ribs. Sickness, loss of appetite, a build-up of fluid in the abdomen, and yellowing of the skin and eyes
Bones Pain or discomfort in the bones
Brain Headaches and sickness, which can often be worse first thing in the morning, weakness in a limb, numbness, tingling or pins and needles
General Weight loss, loss of appetite, stomach pain, blood in faeces (stools), feeling extremely tired, generally unwell

Treatment options8–10

There are currently several different methods for treating advanced melanoma. The treatments may be chosen to help with removing a tumour, or controlling symptoms, or a mixture of both. A treatment plan is chosen based on a number of factors:

  • Where the cancer is on your body
  • Your general health
  • The stage of your cancer
  • Results of blood tests and scans

The list of melanoma treatments below is not exhaustive and is not in any order. If you have any questions about any of these treatment options, please contact your healthcare team.

Surgery – This is the main treatment for melanoma that hasn't spread. Doctors use it to remove the abnormal area of skin and a small area of surrounding skin.

Radiotherapy – Uses high-energy rays to destroy cancer cells. It is used to help shrink your tumour and help control symptoms.

Immunotherapies – Immunotherapies are a group of drugs that work with your body’s immune system, helping it to identify and destroy cancer cells.

Targeted therapies – These work by targeting the differences in cancer cells that help them to grow and survive.

Chemotherapy – Usually you only have chemotherapy if you are unable to have a targeted cancer drug or immunotherapy.

Further information

Melanoma is a complex condition and there is lots more to read about. We recommend visiting the following websites for more information:

Melanoma UK

Melanoma Focus

Cancer Research UK

Macmillan Cancer


  1. Skin Cancer Foundation, Melanoma Overview. Available at:
  2. Cancer Research UK, What is melanoma? Available at:
  3. Cancer Research UK, Risks and causes of melanoma. Available at:
  4. Skin Cancer Foundation, Melanoma warning signs. Available at:
  5. Macmillan Cancer. Staging and Grading. Available at:
  6. Skin Care Foundation, Melanoma Stages. Available at:
  7. Macmillan Cancer, Signs and Symptoms. Available at:
  8. Cancer Research UK, Treatment options. Available at:
  9. Cancer Research UK, Radiotherapy. Available at:
  10. Cancer Research UK, What are targeted cancer drugs? Available at:

Supporting documentation

KEYTRUDA® (pembrolizumab)

Summary of Product Characteristics | Patient Information Leaflet

GB-OOC-00322 | Date of Preparation: October 2020