What is melanoma?
Melanoma is a type of skin cancer which usually occurs on the parts of the body that have been overexposed to the sun. Rare melanomas can occur inside the eye or in parts of the skin or body that have never been exposed to the sun.
Melanoma is the third most common cancer diagnosed in Australia, which along with New Zealand has the world's highest incidence rate for melanoma. Melanoma is more commonly diagnosed in men than women. The risk of being diagnosed with melanoma by age 85 is 1 in 13 for men compared to 1 in 21 for women.
In 2016, 14,485 new cases of melanoma were diagnosed in Australia, accounting for nearly one in ten cancer diagnoses.
In Australia in 2018, there were 1429 deaths due to melanoma.
Often melanoma has no symptoms, however, the first sign is generally a change in an existing mole or the appearance of a new spot. These changes can include:
colour - a mole may change in colour, have different colour shades or become blotchy
size - a mole may appear to get bigger
shape - a mole may have an irregular border or may increase in height
elevation - the mole may develop a raised area
itching or bleeding.
Other symptoms include dark areas under nails or on membranes lining the mouth, vagina or anus.
New moles and spots will appear and change during childhood, adolescence and during pregnancy and this is normal. However, adults who develop new spots or moles should have them examined by their doctor.
Causes of melanoma
Melanoma risk increases with exposure to UV radiation from the sun or other sources such as solariums, particularly with episodes of sunburn (especially during childhood).
Melanoma risk is increased for people who have:
unprotected sun exposure
a history of childhood tanning and sunburn
a pattern of short, intense periods of exposure to UV radiation
increased numbers of unusual moles (dysplastic naevi)
depressed immune systems
a family history of melanoma in a first degree relative
fair skin, a tendency to burn rather than tan, freckles, light eye colour, light or red hair colour
had a previous melanoma or non-melanoma skin cancer.
Diagnosis of melanoma
Melanoma can vary in the way it looks. The first sign is usually a new spot or change in an existing mole.
If you do notice any changes to your skin, your doctor will examine you and carefully check any spots you have identified as changed. Your doctor will use a handheld magnifying instrument (dermascope) and consider the criteria known as “ABCDE”. Further tests may be carried out by your GP or you may be referred to a specialist (dermatologist).
- A - Asymmetry, irregular
- B - Border, uneven
- C - Colour
- D - Diameter (usually over 6mm),
- E - Evolving (changing and growing).
If the doctor suspects that a spot on your skin could be melanoma, an excision biopsy is carried out with the removal of the whole spot. This will then be examined under a microscope by a specialist to see if there are any cancer cells.
Checking lymph nodes
Your doctor may feel the lymph nodes near the melanoma to see if they are enlarged as melanoma can sometimes travel via the lymph vessels to other parts of your body. Your doctor may also recommend a biopsy to take a sample of the cells from an enlarged lymph node for further examination under a microscope.
Treatment for melanoma
The most important feature of a melanoma in predicting its outcome is its thickness.
- stage 0 is less than 0.1mm
- stage I less than 2mm
- stage II greater than 2mm
- stage III spread to lymph nodes and
- stage IV distant spread.
The presence of ulceration also predicts a poor outcome. If distant spread is suspected, CT scans of the chest, abdomen and pelvis are performed. The blood test LDH can sometimes be useful to assess metastatic disease.
Surgery can be curative for thin melanomas and requires that the melanoma be removed with at least 1-2cm of normal skin around it. If the draining lymph nodes are involved they are removed.
If the melanoma has spread to the lymph nodes, you will have a lymph node dissection or lymphadenectomy to remove them. If lymph nodes have been removed, your neck, arm, or leg may swell. This is called lymphoedema.
If there is a risk that the melanoma could come back, you may be offered additional treatments. These can include immunotherapy and targeted therapy.
Treatment for advanced melanoma, where the cancer has spread to lymph nodes, internal organs or bones, may include surgery, radiation therapy targeted therapy or immunotherapy.
Surgery may be used to treat metastatic melanoma that involves other parts of the skin. Surgery may also still be possible if the melanoma has spread to other organs but will depend on the part of the body that is affected.
Radiation therapy may be of benefit in treating some forms of melanoma. It may be used:
- when cancer has spread to the lymph nodes
- after surgery to prevent the cancer returning
- in combination with other treatments
- as palliative treatment.
Targeted therapy drugs attack specific genetic changes (mutations) that allow melanomas to grow and spread while minimising harm to healthy cells. It is most commonly used for melanomas that have spread to other organs or if it has come back after treatment.
Immunotherapy uses drugs to stimulate the body's immune system in order to recognise and fight melanoma cancer cells. Ipilimumab, nivolumab and pembrolizumab are three immunotherapy drugs approved for treatment of advanced melanoma.
In some cases of melanoma cancer, your medical team may talk to you about palliative care. Palliative care aims to improve your quality of life by alleviating symptoms of cancer.
As well as slowing the spread of melanoma, palliative treatment can relieve pain and help manage other symptoms. Treatment may include radiotherapy, chemotherapy or other drug therapies.
Treatment TeamDepending on your treatment, your treatment team may consist of a number of different health professionals, such as:
- GP (General Practitioner)- looks after your general health and works with your specialiststo coordinate treatment.
- Dermatologist- specialises in preventing, diagnosing and treating skin diseases.
- Reconstructive (plastic) surgeon- performs any complex reconstructive surgery that restores or repairs the body's appearance and function.
- Medical oncologist- prescribes and coordinates the course of chemotherapy.
- Radiation oncologist- prescribes and coordinates radiation therapy treatment.
- Physiotherapist/occupational therapist- help with physical and practical problems such as restoring movement and mobility after treatment.
- Surgeon- Surgeon which can be a general surgeon, a surgical oncologist to manage complex skin cancers or a plastic surgeon trained in complex constructive techniques, including surgery if the cancer has spread..
Screening for melanoma
There is no organised screening program for melanoma. However, individuals at high risk of melanoma should be taught to check their skin for irregular or changing lesions, and have annual checks by a dermatologist.
Download Cancer Council's skin cancer identification poster to help identify potential skin cancers:
Avoid sunburn by minimising sun exposure when the UV Index is 3 or above, and especially in the middle of the day when UV levels are most intense. Seek shade, wear a hat that covers the head, neck and ears, wear sun protective clothing and close-fitting sunglasses, and wear an SPF30 sunscreen. Avoid using solariums.
Work outdoors? Use UV protection every day - Download the PDF here:
Prognosis for melanoma
Prognosis refers to the predicted outcome of a disease. It is not possible for a doctor to predict the exact course of the disease. An individual's prognosis depends on the type and stage of cancer, as well as their age and general health at the time of diagnosis.
Melanoma can be most effectively treated in its early stages when it is still confined to the top layer of the skin.
Understanding Melanoma, Cancer Council Australia, © 2019. Last medical review of source booklet: January 2019.
Australian Institute of Health and Welfare (AIHW). Australian Cancer Incidence and Mortality (ACIM) books: Stomach cancer. Canberra: AIHW.
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