What is Melanoma?

Melanoma is possibly the most serious form of skin cancer and can begin within an existing mole or can also appear out of the blue.

Melanoma is known to spread very quickly once it penetrates below the surface of the skin, which means it is very important to identify Melanoma as early as possible.  Early Melanoma may not have any noticeable symptoms but they usually appear as a changed or new mole.  Although not all show these characteristics, symptoms can often be described by the ABCD system:

Asymmetry – two halves of the mole are different from one another

Border – the edges are poorly defined.  The mole is ragged, notched, blurred or an irregular shape

Colour – the color is uneven with shades of black, brown and tan.  Melanomas may also be white, grey red, pink or blue

Diameter – there is a change, particularly an increase in size.  Melanomas are usually bigger than the end of a pencil (6mm)

It is important to note that not all melanomas fit these ABCD rules as described above.

There are two common staging systems used to determine the severity of Melanoma, the Breslow thickness and Clark Level.

The Breslow thickness measures the vertical height of the melanoma growth in millimeters, from the very top to the area of deepest penetration into the skin.  In general the higher the Breslow thickness is, the worse the prognosis.

The Clark Level refers to how deep the melanoma growth has penetrated into the different layers of the skin. They are defined as follows:

Level I – confined to the epidermis (top-most layer of skin); called ‘in situ’ melanoma, 100% cure rate at this stage.

Level II – invasion of the papillary (upper) dermis

Level III – filling of the papillary dermis, but no extension into the reticular (lower) dermis

Level IV – invasion of the reticular dermis

Level V – invasion of the deep, subcutaneous tissue

With early treatment, where the melanoma has not spread beyond the superficial layers of the skin, the prognosis is excellent and disease is often curable.  But once it has become invasive and spreads to other parts of the body, it is very difficult to treat and can be fatal.

If you notice a mole that is different to others, changes shape, size or colour, new skin lesions or a mole that itches and bleeds, you should seed professional advice as soon as possible.