Malignant Melanoma Explained
What is a melanoma?
Malignant melanoma of the skin is a skin cancer, which affects the pigment producing cells in the skin.
Who gets a melanoma?
Exposure to sunlight, either via sunbeds or due to getting sunburnt, especially in childhood or the first 20 years of your life, is the most important cause of melanoma.
It is possible that there is an inherited tendency to develop melanomas, in some families, but this is not fully understood as yet. Also, patients on drugs that suppress their immune system, eg following a transplant, may be at increased risk of developing a melanoma.
What does a melanoma look like?
Appearances can vary immensely and the diagnosis can be difficult to make, especially if you are not a specialist, experienced in skin examination.
There are different types of melanoma, but they are not mutually exclusive. Some melanomas show overlapping features of the different types:
- Nodular type – typically a dark coloured lump which has grown rapidly. It may be composed of different colours and may or may not be painful, or have bled. It may or may not have arisen from an existing mole.
- Superficial spreading type – a flat, dark coloured or unevenly coloured patch with an irregular outline. This is the commonest type of melanoma.
- Lentigo maligna melanoma – this tends to grow slowly and occur on the face. There may have been a brown patch which has changed colour, size and shape gradually.
- Acral lentiginous type – this is a rare form of melanoma, which occurs on the hands or feet.
There are also other rare melanomas – and you can develop melanomas in any other organ in your body, as well as your skin. (In medical terms, the skin is an organ, like your liver and kidneys).
What is the treatment?
The main treatment for melanoma is surgical.
Any lesion (the lump or mole) where there are suspicions it may be a melanoma should be removed completely from the skin by a consultant dermatologist experienced in skin surgery. The lesion specimen which has been removed is then examined carefully under a microscope, to assess the type of melanoma and the depth of invasion of the cells in the skin, so that the most suitable further treatment can be planned.
In the majority of cases, the only treatment required is to remove a rim of normal skin around the original scar to ensure all the melanoma cells are removed and therefore reduce the risk of it growing back. This is called a ‘Wide Local Excision.’ This may be performed by your consultant dermatologist or a plastic surgeon, depending on the position of the melanoma. Your consultant dermatologist will discuss this with you.
What happens afterwards
This depends on the thickness of the melanoma or the lowest level within the skin that melanoma cells are found. Thin melanomas (less than 1mm in depth) require nothing other than having the wide local excision.
Thicker melanomas (over 1mm in depth) are automatically referred to a specialist melanoma clinic and your consultant dermatologist will tell you where this will be. Here they may perform a procedure called a ‘Sentinel Lymph Node Biopsy’, to assess whether the melanoma has spread. In a few cases, a scan may be recommended as well, to check whether cancer cells have spread to other parts of the body.
If the melanoma has spread then chemotherapy may be recommended.
Will I be cured?
95% of cases of thin melanomas (less than 1mm in depth) have no further problems and overall, three quarters of people who have a melanoma removed, go on to have no further problems.
Will I need follow ups?
This depends on the type of melanoma you have had.
For thin melanomas (less than 1mm in depth), you may only need a follow up every 6 months, for 1 year. The appointment is mainly to check that the tumour has not grown back or spread and to check all your skin to ensure that no new skin cancers have developed.
For thicker melanomas (greater than 1mm), you will normally be seen more frequently, for more years, with visits usually split between the specialist melanoma clinic and your local consultant dermatologist.