Melanoma is responsible for most skin cancer deaths and is unfortunately on the increase. Australia has the highest rate of melanoma in the world; one in 14 Australian males and 1 in 22 females will develop melanoma in their lifetime (to age 85).Early diagnosis is extremely important, as early treatment is usually curative (95%).
What does treatment involve?
Melanoma treatment requires surgery. The accepted and recommended treatment of a melanoma involves:
- Excision of the melanoma with an appropriately wide margin of skin
- Regular follow up appointments, which involve checking for enlarged lymph nodes, checking for recurrence at the site of the original melanoma, and checking for new melanomas
- Regular full skin checks, with dermoscopy (surface skin microscopy) and consideration of digital mapping photography
Removing an appropriate margin of skin with the melanoma reduces the likelihood of the melanoma recurring at the initial site. The recommended margins vary from 0.5cm to 2cm according to the depth of the melanoma, which is measured under a microscope by the pathologist. It is simpler and less disfiguring to take a large margin if the melanoma is on the back than if it is on the eyelid, so the site of the melanoma is also taken into consideration. If the melanoma is located on the nail bed (under the nail) then amputation of the end of the finger or thumb is recommended.
The importance of melanoma thickness
Melanoma thickness is the most important determinant of risk with a primary melanoma. A pathologist measures the thickness when examining a melanoma biopsy. The thickness is measured in millimetres from the skin surface to the deepest part of the melanoma.
In Situ and Invasive
If your melanoma has been called "in situ", melanoma cells are found only in the outer layer of skin cells and have not penetrated deeper tissues (the dermis). An in situ melanomas is not considered to have the potential to have spread or to be life threatening, provided it has been removed. If it is left in place it can grow deeper and then it would have the potential to spread and to be life threatening. Invasive melanomas have penetrated to the dermis. The deeper the penetration the greater the risk of spread via lymph or blood vessels.
Stage 1: cancer is found in the upper part of the skin (the epidermis and/or the upper part of the dermis) but has not spread to the lymph nodes. The tumour is usually <1 mm thick. This stage also includes tumours up to 2 mm thick if they are not ulcerated.
Stage 2: cancer has spread to the deeper part of the dermis but not through the skin or into lymph nodes. The tumour is <4 mm thick.
Stage 3: the tumour may be larger or smaller than 4 mm and/or may have spread to deeper layers of the skin. There may be additional tumour growths between the original site and nearby lymph nodes; melanoma cells may have spread to surrounding lymph nodes.
Stage 4: the tumour cells have spread to other organs or lymph nodes far away from the original site.
There have been significant changes in the treatment of advanced melanoma in recent years, with researchers at the Peter MacCallum Cancer Centre stating in 2014 that "the last 3 years have seen a seismic shift" in the management of patients with Stage 4 melanoma. For more information click here (link to full text article in ANZJSurg).
Sentinel lymph node biopsy (SLNB)
The role of sentinel lymph node biopsy (SLNB) in melanoma has been heavily studied to determine whether SLNB should be recommended or not, and to whom it should be recommended. The results of the landmark MSLT-I trial were published in February 2014 in the New England Journal of Medicine. The study concluded that SLNB provides important prognostic information, and that SLNB based management "prolongs disease-free survival for all patients and prolongs distant disease-free survival and melanoma-specific survival for patients with nodal metastases from intermediate thickness melanomas."
If you have a melanoma that is 1.0mm thick or greater you should discuss with your surgeon whether you should have a sentinel lymph node biopsy. A SLNB cannot be performed after you have had a "wide local excision" of your melanoma, so the decision regarding whether to have a SLNB or not is made between your first biopsy surgery and your second (wider) excision surgery.
Sentinel lymph node biopsy is not usually a complex or difficult operation, but it can have complications and after-effects which you should discuss with your surgeon before the surgery. Complications that can happen close to the time of surgery include infection, bleeding, the development of a seroma (a collection of lymphatic fluid that may require repeated drainage), delayed wound healing, pain and numbness of the overlying skin. One of the later complications that can develop is lymphoedema, although this is uncommon because only a couple of lymph nodes are removed.
Melanoma and the lymph nodes
Melanoma may have already spread to the lymph nodes at the time of diagnosis, or it may occur in the years after diagnosis. Importantly, this is not the case for the majority of people.
Usually the first sign that melanoma has spread to the lymph nodes is an enlarged lump. This is usually painless, although occasionally it can be painful if there is rapid growth or haemorrhage (bleeding) within the lymph node. The lymph node site that is closest to the original site of the melanoma is most commonly involved. For example, if the melanoma was on your hand or arm the affected lymph node site will usually be the armpit. If the melanoma was on your leg the affected lymph node site will usually be the groin. If the melanoma was on your ear, the affected lymph node site will usually be the neck.
If you have had a melanoma and you notice a new lump in a lymph node site then you should draw this to the attention of your doctor within a week. Commonly a scan will be performed, you will be referred to a melanoma specialist and a biopsy will be recommended, using a needle to aspirate cells from the lump which are then examined under a microscope looking for melanoma.
Lymph node dissection (or "completion lymph node dissection")
If melanoma cells are found in a sentinel lymph node biopsy or if there are other signs that the melanoma has spread to your lymph nodes then removal of these lymph nodes is recommended. This operation has many names - including a "lymph node dissection", or "lymph node clearance", an "axillary dissection" (in the arm pit), a "groin dissection" (in the groin) or a "neck dissection" (for the neck). The aim is to remove all the lymph nodes in the area, thus removing all the possible sites of melanoma in the area. If the melanoma has not spread any further then the operation can theoretically be curative.
Lymph node dissection can have complications and after-effects which you should discuss with your surgeon. Complications that can happen close to the time of surgery include infection, bleeding, the development of a seroma (a collection of lymphatic fluid that may require repeated drainage), delayed wound healing, pain and numbness of the overlying skin. One of the later complications that can develop is lymphoedema. This complication occurs much more frequently with full lymph node dissection than with a sentinel lymph node biopsy, because the operation is much more extensive.
What about chemotherapy, radiotherapy or other forms of treatment?
Chemotherapy, radiotherapy, CT scans, MRIs, lymph node biopsies and blood tests are not a routine part of melanoma treatment. If you have advanced melanoma or suspicious symptoms or signs your doctor may organise additional tests. If you are taking part in a trial you will often have scans before, during and after the trial, so that any changes can be detected. Routine scans have not been found to be worthwhile for people who have been diagnosed with early melanoma.
Do I need to go to a specialist melanoma unit or centre?
Assessment at specialist melanoma unit or centre is not required for people with an uncomplicated melanoma. Most melanoma patients in Australia are not treated at such a unit.
If you have a melanoma that is advanced or unusual then assessment by a melanoma unit may well be of benefit and we will refer you to a specialist Multi-Disciplinary Meeting for discussion and recommendations about the best treatment for you. Melanoma units have experts from multiple fields including dermatology, palliative care, nursing, medical oncology, radiation oncology, surgical oncology, psychology, head and neck surgery, neurosurgery, plastic surgery and general surgery. Many melanoma units undertake research into melanoma treatments and participate in trials that cannot be accessed elsewhere. These trials are generally only applicable to patients with advanced melanoma.
Melanoma units also have staff and dedicated melanoma nurses who are very experienced in dealing with melanoma patients and their families. Many people find the counselling, psychological support and individual advice offered of immense value when coming to terms with a life threatening or potentially life threatening cancer.
Click here to read about melanoma prevention
Melanoma Patients Information Page
Multidisciplinary treatment centres in Victoria
Peter MacCallum Cancer Centre Melanoma and Skin Cancer Service
Victorian Melanoma Service at the Alfred Hospital
MoleMap : full body photography and dermatoscopy services where the images are examined by qualified dermatologists. Please note that no melanoma surveillance service is 100% accurate and MoleMap is not a substitute for seeing your doctor or specialist for regular skin checks, especially if you are at high risk of developing melanoma or other skin cancers.