1
Cancer Council, Victoria – Helpline: 13 11 20 on Monday to Friday from 8.30am to 6pm.
Melanoma
Tuesday 30 June, 2009
Reviewed by: Prof. John Kelly, Dermatologist; Mr David Speakman, Head, Melanoma and Skin
Service, Peter MacCallum Cancer Centre
Taken from
Melanoma booklet (880kb)
The skin
The skin has many important functions. It protects us from injury, cools us when we
get too hot and prevents us from becoming dehydrated.
The skin has 2 main layers. The top layer is called the epidermis. This layer contains,
among other things, melanocytes-cells that produce melanin, the substance that
gives skin its colour. The layer underneath the epidermis is called the dermis. The
dermis contains the roots of hairs, glands that make sweat and oil, blood and lymph
vessels and nerves.
Skin cancer
Like all body tissues, the skin is made of tiny ‘building blocks' called cells. These cells can sometimes
become cancerous. One cause is too much exposure to ultraviolet (UV) radiation.
The epidermis contains 3 different types of cells:
1. squamous cells,
2. basal cells and
3. melanocytes.
Skin cancers are named after the type of cell they start from. The 3 main types of skin cancer are
basal cell cancer, squamous cell cancer and melanoma, which is the most serious skin cancer.
© Cancer Council Victoria 2011 - www.cancervic.org.au
2
Cancer Council, Victoria – Helpline: 13 11 20 on Monday to Friday from 8.30am to 6pm.
Melanoma
Melanoma develops from melanocytes (pigment cells). These cells are the cause of freckles and moles
on the skin and produce the colour of a suntan.
Melanoma usually occurs on parts of the body that have been sunburned. However, melanomas can
sometimes start in parts of the skin or other parts of the body that have never been exposed to the
sun.
Melanoma can grow quickly. If detected early, most melanomas are curable. If they're not detected
until later, they can become more serious and may spread to other parts of the body. A melanoma
may appear as a new spot on normal skin, or develop from an existing mole.
Melanomas usually begin as a flat spot that changes in size or shape or colour over months. While they
remain flat they are generally curable. They usually remain flat for six to 12 months. Later, melanomas
become bigger, irregular in shape and often darker in colour.
A less common type of melanoma (called nodular melanoma) is not flat, but is raised from the start.
These melanomas are often pink or red, and grow quickly. Not all melanomas are dark or black in
colour.
Causes of melanoma
Melanoma and other skin cancers generally develop because of too much exposure to UV radiation.
Each time unprotected skin is exposed to the sun's UV radiation or other sources of UV radiation, such
as solariums, changes take place in the structure of the cells. Too much UV radiation causes the skin to
become permanently damaged. The damage increases with each exposure.
Melanoma is not contagious: you can't catch it from someone else.
People at increased risk of melanoma have one or more of the following:








fair skin that burns easily and does not tan
a fait complexion
lots of moles on the skin
a number of large, irregularly shaped and unevenly coloured moles (called dysplastic naevi)
previous melanomas
a history of many sunburns
other people in the family who have had melanoma (a ‘family history')
being older (risk increases with age).
Sunburn and too much exposure to UV radiation during childhood greatly increase the risk of
melanoma.
How common is melanoma?
Australia has the highest rate of skin cancer in the world. Each year over 2100 people in Victoria are
diagnosed with melanoma.
Melanoma is more common in people with fair complexions than people with naturally darker skins.
Melanoma is diagnosed more often in older adults. It sometimes occurs in younger adults and
teenagers. It's rarely seen in children.
© Cancer Council Victoria 2011 - www.cancervic.org.au