This information has been prepared to help you understand more about melanoma.
Many people feel understandably shocked and upset when they are told they have melanoma. This information is intended to help you understand the diagnosis and treatment of this type of cancer.
We cannot advise you about the best treatment for you. You need to discuss this with your doctors. However, we hope this information will answer some of your questions and help you think about the questions you want to ask your doctors or other health carers.
The skin is the largest organ in the body. It protects the body from injury, prevents dehydration and regulates body temperature. The skin is made up of two main layers called the dermis and the epidermis.
The lower layer (the dermis) contains roots of hairs, glands that make sweat, blood and lymph vessels, and nerves. The outer layer (the epidermis) contains three different types of cells:
Squamous cells: flat cells that are packed tightly to make up the top layer.
Basal cells: tall cells that make up the lower layer.
Melanocytes: cells that produce a dark pigment called melanin.
What is melanoma?
Melanoma is a type of skin cancer that usually occurs on parts of the body that have been overexposed to the sun. There are three main types of skin cancer that are named according to the cells that are affected (squamous cell carcinoma, basal cell carcinoma and melanoma).
Melanoma starts from the melanocytes which are the cells in the skin that produce melanin (the skin colour or pigment). Melanocytes are the cause of freckles and moles on the skin and produce the brown colour of a suntan. For men, melanoma is more common on the back; whereas women get more melanomas on their legs than men.
In rare cases, melanoma may start in a part of the skin or other part of the body that has never been exposed to the sun, such as the nervous system, eye and mucous membrane.
Although melanoma is the least common type of skin cancer, it is the most serious. If melanomas are not treated early, they can grow quickly and spread to the dermis, lymph vessels, and other parts of the body.
Types of melanoma
Skin melanomas are categorised according to how thick they are, how far they have spread and the way they look. There are four main types of skin melanoma:
This type of melanoma starts as a brown or black spot that spreads across the epidermis. It is the most common type of melanoma (making up almost 65% of cases) and can become dangerous when it invades the lower layer of the skin.
Often a raised lump on the skin that is very dark brownish-black or black in colour, but can also be pink, red, or have no pigment at all. Nodular melanoma makes up approximately 15% of melanomas.
This type of melanoma begins as a large freckle (lentigo maligna) in an area of skin that gets a lot of sun exposure, such as the face and upper body. This type of cancer grows slowly and superficially over many years and is common in older people. LMM makes up about 10% of melanomas.
A rare type of melanoma often found on the palms of the hands and soles of the feet or under the nails.
How common is melanoma?
If you would like to read any facts or statistics about melanoma, please refer to the Cancer Institute NSW website:
What is the cause?
The main cause of melanoma is exposure to ultraviolet (UV) radiation from the sun and other sources, such as tanning machines in solariums. Each time your unprotected skin is exposed to UV radiation, it changes the structure of the cells and what they do.
Exposure to UV radiation permanently damages the skin. This damage will add up over time. The most important years for sun protection are during childhood. Exposure to the sun during these years greatly increases the chance of getting melanoma because the damaged cells have much longer to grow and develop into cancer.
In rare cases, melanoma happens by chance and is not linked to sun exposure.
Who is most at risk?
People with high exposure to UV radiation have the highest risk of developing melanoma. However, other factors may also increase your risk:
- Having a fair complexion – some people have skin that is more sensitive to UV radiation. You have a higher risk if you have pale or fair skin, burn easily, have skin that doesn’t tan or have light-coloured eyes.
- Having a lot of moles – if you have more than 10 moles on your arms and more than 100 on your body you should have your skin checked regularly by your GP or a skin specialist (dermatologist).
- Childhood tanning/sunburn – too much exposure before the age of 15 significantly increases your risk of melanoma in later life because damaged cells have more time to develop into cancer.
- Occasional heavy sun exposure – if you occasionally get heavy sun exposure (e.g. on weekends or on holidays) you will be at increased risk.
- Getting older – although melanoma is the most commonly diagnosed cancer in 15-44 year olds, it is more common in people over 50 years of age.
- Personal history of cancer – if you have had a melanoma or other type of skin cancer (BCC or SCC) your risk will be higher than someone who has not.
- Family history of cancer – in a small number of people (5-10%), melanoma may be caused by an inherited faulty gene. Melanoma is more likely to be caused by an inherited faulty gene if two or more close relative on the same side of your family have (or had) melanoma or if a close family member has been diagnosed with melanoma before the age of 40.
What are the symptoms?
Melanomas can vary greatly in the way they look. The first sign of a melanoma is usually a new spot or a visible change in an existing freckle or mole. The change may be in:
Colour: The freckle or mole may appear blotchy with a wide variety of colours, such as brown, black, blue, red, white and/or grey.
Size: The freckle or mole begins to get, or keeps getting, larger.
Shape or border: An irregular edge (scalloped or notched) or lack of symmetry is a sign of melanoma. The mole may increase in height or become scaly.
Itching or bleeding: If a mole itches or bleeds it may have become a melanoma.
It is normal for new moles to appear and change during childhood and pregnancy. However, in adults a new mole could be a melanoma and you should have it checked by your doctor immediately. If you notice any changes in existing moles or freckles you should also bring it to the attention of your doctor, even if you have had that mole checked in the past.
Initially, a suspicious spot or mole will be examined by your doctor. The first examination is usually done by your GP, who can refer you to a dermatologist or surgeon if necessary. The suspicious mole will be examined using a magnifying instrument called a dermoscope. During the same appointment, your GP will probably look at your other moles, feel nearby lymph nodes and ask about your history, and your family’s history, of melanoma.
Excision biopsy (removing the mole)
If your GP suspects that a spot or mole on your skin may be a melanoma, they will probably conduct a biopsy or send you to a dermatologist or surgeon to have a biopsy. A biopsy is a quick and simple procedure that is done under a local anaesthetic.
The GP, dermatologist or surgeon who conducts the biopsy will use a scalpel to cut out the mole and some surrounding tissue. You will probably require a couple of stitches.
The tissue sample will be sent to a laboratory, where a tissue specialist (histopathologist) will examine it under a microscope. If the cells are found to be cancerous, you will probably need further surgery to remove the cancer or find out how far it has spread.
If it is confirmed that you have melanoma, your doctor will investigate whether the cancer has spread to your lymph nodes. Melanoma can travel through the lymph vessels to other parts of the body. Your doctor will probably conduct one or more of the following types of biopsies and scans:
A sample of cells is taken by inserting a needle into a suspicious lymph node. The tissue is drawn into the syringe and examined under a microscope to see if it contains cancer cells.
A small amount of radioactive fluid is injected into the area where the melanoma was removed. The purpose of this type of biopsy is to locate the lymph node that drains fluid from the area where the melanoma was found.
After about half an hour, a hand-held machine called a gamma counter is passed over the area to see which node has absorbed the radioactive fluid first. This is known as the sentinel node and will be removed in a simple operation to check for cancer cells. If cancer cells are found, the remaining nodes in the area will be removed to try and stop the cancer from coming back in the same area.
A CT scan (also called a CAT scan) uses X-ray beams to take pictures of the inside of your body. You may be injected with a dye that makes your organs appear white on the scans. A CT scan is painless and is used to see if the cancer has spread.
An MRI scan uses radio waves and a powerful magnet to create a cross-sectional image of the body. The image can show the difference between healthy and diseased tissue. MRI scans makes better images of organs and soft tissue than other scanning techniques, such as CT scans or X-rays and are especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones.
MRI scans are painless, however some people find lying in the scanner noisy and claustrophobic.
PET scans use the emissions from a mild, radioactive glucose solution to create images that explain how certain organs or systems in the body are functioning. The solution circulates throughout the body and is taken up by actively dividing cells, such as cancer cells. It may take several hours to prepare for and have a PET scan.
PET scan are usually not necessary in thinner melanomas because there is a very low risk that the cancer has spread to internal organs. Even when tumours are more than 4 mm deep, the internal spread, if it is present, is likely to be too small to be detected by a PET scan.
Staging the melanoma
Working out how far the cancer has spread is called staging. Staging helps your doctor recommend the best treatment for you.
Stages 1-2: The melanoma has not moved beyond the starting point on the skin (primary site). This is called localised cancer.
Stage 3: The melanoma has spread to lymph nodes near the primary site.
Stage 4: The melanoma has spread (metastasised) to other parts of the body.
Measuring the depth of a melanoma
The depth of the melanoma is important because the deeper the cancer cells have grown into the skin, the more likely it is the cancer will come back (recur) or spread to the lymph nodes or internal organs.
If the cancerous cells are only in the uppermost skin, and have not penetrated into deeper tissues, this is called a tumour in-situ. In some cases, biopsy may be all the treatment that is needed. If the tumour has penetrated further into the skin, more tissue and skin may need to be removed from around the melanoma.
Your pathology report will probably provide information about your Breslow thickness and Clark level. The Breslow thickness is a measure of the thickness of the tumour according to four categories, from less than 1mm (accounting for most melanomas) to more than 4mm. The Clark level describes how deeply the cancer has gone into the layers of the skin and is rated from 1 to 5 (1 being the shallowest and 5 the deepest).
Prognosis means the expected outcome of a disease. You may want to discuss your prognosis with your doctor. It is important to understand that it is not possible for any doctor to predict the exact course of your disease. However, they will be able to discuss your likely prognosis based on factors such as the type of melanoma you have, the rate and depth of tumour growth, how well you respond to treatment, and other factors such as your age and medical history.
In Australia, more than 85% of people with melanoma are cured by surgery. With early detection and treatment, the percentage of people cured has grown steadily over the past 20 years. Early diagnosis is the most important factor influencing prognosis. Melanoma can be most effectively treated when it is still confined to the epidermis (the top layer of the skin), before it spreads to draining lymph nodes or other organs.
Which health professionals will I see?
You will be cared for by a range of health professionals who specialise in different aspects of your treatment. Depending on the type and stage of your cancer you may not see all of the health professionals listed below. Most people with melanoma will only need to have the melanoma surgically removed and will not need to see medical or radiation oncologists.
Health professionals for people with early melanoma include:
- General practitioner (GP) – conducts your initial examination and refers you to the relevant specialist(s).
- Dermatologist – specialises in the diagnosis and treatment of skin disorders.
- Histopathologist – examines tissue to diagnose cancer.
- Surgeon – performs operations to remove the melanoma.
- Plastic surgeon – specialises in surgery to reconstruct the appearance of the body.
- Specialist nurses – support you throughout your diagnosis and treatment.
In addition, people with advanced melanoma will see some or all of the following health professionals:
- Medical oncologist – prescribes and coordinates the course of chemotherapy.
- Radiation oncologist – prescribes and coordinates the course of radiotherapy.
- Dietitian – recommends an eating plan for you to follow while you are in treatment and recovery.
- Social worker, counsellor, psychologist, and physiotherapist – link you to support services and help you with emotional, physical and practical problems.
- Palliative care team – help you and your family with any needs you have, including support at home.
Most early stage cancers are treated with surgery. Often this is the only treatment needed. Patients with more advanced cancer may have a combination of surgery, radiotherapy and chemotherapy. Your doctor will advise you on the best treatment for you based on the stage of the melanoma and what you want.
Treatment for early melanoma
Melanoma that is found early can usually be treated successfully with surgery. The surgical procedures that you may undergo are:
Melanomas are always surgically removed. A wide local excision involves the removal of the area where the melanoma was and a small amount of normal skin surrounding it. This area, called a safety margin, is removed to ensure that all the cancer cells have been removed. A pathologist examines the tissue and determines whether the margins are clear or whether you will need further treatment.
A wide local excision is usually done under a local anaesthetic, however you may be given a general anaesthetic if you have a sentinel node biopsy. Your wound will probably be drawn back together with stitches. If the wound is too big to close with stitches your surgeon may cover it using skin from another part of your body (skin flap or skin graft).
If the melanoma has spread to your lymph nodes, they will also be removed. The procedure to remove lymph nodes is called a lymph node dissection or a lymphadenectomy. The location of your melanoma will determine which lymph nodes are removed. There are large groups of lymph nodes in the neck, armpits and groin.
Adjuvant therapies may be given after surgery if there is a high risk of your melanoma coming back. The major adjuvant therapies are known as biological therapies, which stimulate the body’s immune system to fight the cancer.
Treatment for advanced melanoma
If you are diagnosed with advanced melanoma (also known as metastatic or secondary melanoma) it means that the cancer has spread to distant skin sites, lymph nodes or internal organs. You will probably undergo a combination of surgery, radiotherapy, biological therapies and chemotherapy.
Like early stage melanoma, advanced melanoma may be treated with a wide local excision and lymph node dissection. A wide local excision is usually possible if the cancer has spread to other parts of the skin, but may still be conducted if the melanoma has spread to internal organs.
Radiotherapy uses high-energy X-rays to kill cancer cells or injure them so they cannot multiply. It is used to prevent the melanoma from coming back or to destroy any cancer cells that may have spread to the lymph nodes.
Radiotherapy for melanoma is usually given over 1-4 weeks, however the exact length of your treatment will depend on the size and location of the tumour, and your general health.
Chemotherapy uses drugs to kill or slow the growth of cancer cells. These drugs are called cytotoxic drugs. Chemotherapy kills rapidly dividing cells such as cancer cells while doing the least possible damage to healthy cells.
Chemotherapy may be given to cure or slow the growth of melanoma. It is usually given over 3-12 months. However, the number and frequency of treatment sessions will vary according to the type of melanoma you have and which cytotoxic drug(s) are used.
Targeted therapies are a relatively new development which aid the treatment of advanced melanoma. Targeted therapies are substances that can identify differences between cancer cells and normal cells by selectively targeting proteins in the cancer cells that signal the cancer cell to grow. They have been shown to help specific groups of people with melanoma; for example, people who have a change in a gene called BRAF.
Biologic therapies may also be used for the treatment of advanced melanoma. These drugs are usually given intravenously (injected into a vein) and are able to stimulate the body’s immune system to fight the melanoma.
Palliative treatment helps improve quality of life by alleviating the symptoms of cancer without trying to cure the disease. Palliative treatment may include radiotherapy, chemotherapy and other medication and is particularly important for people with advanced cancer.
Sometimes treatment is concerned with pain relief and stopping the spread of cancer. In other cases, it manages emotional symptoms of cancer.