WHAT IS A MELANOMA? IS IT DANGEROUS?
Melanoma is a serious form of skin cancer that occurs when a tanning cell (Melanocyte) in the epidermis of the skin becomes cancerous. Melanoma is the fifth most common cancer in Australia and the sixth commonest in the USA. The number of melanoma cases diagnosed annually is increasing faster than for any other cancer. Using recent figures from Australia, it's estimated that 1 in 25 Caucasian people in South Africa will develop a melanoma during their lifetime. If left untreated, melanoma can spread (metastasise) to other parts of the body and this can be fatal. Fortunately, when detected at an early stage, melanoma treatment is often effective in limiting the spread of the disease and curative in a significant percentage of people.
CAUSES OF MELANOMA
ULTRAVIOLET RADIATION AND THE SUN
The biggest cause of melanoma is damage to one's skin by ultraviolet radiation from the sun (sunburn). Ultraviolet radiation directly damages the DNA in one's tanning cells and if this causes activation of a cancer gene then a melanoma will result. Multiple sun burns (especially severe ones with blistering) over one’s lifetime significantly increase one’s risk of getting a melanoma. The effect of sun burns is cumulative. Frequent use of sun beds (which have very high intensity ultraviolet light) has been estimated to increase the risk of developing a melanoma by 2.5 times.
DYSPLASTIC NAEVUS SYNDROME
Much less frequently there is a significant genetic component to the development of a melanoma. People with an increased genetic risk of developing melanoma have multiple abnormal looking freckles (dysplastic naevi) and this is called the Dysplastic Naevus Syndrome. Mole mapping is recommended for these patients.
PREVENTING FURTHER MELANOMAS
People who have had melanoma are at an increased risk of developing another melanoma. The development of a melanoma is a sign that there has been enough damage to the skin for a melanoma to have occurred. It also means that there are other damaged cells that may be close to turning into melanomas. Any further damage by ultraviolet light from the sun may be enough to convert these damaged cells into melanoma cells so it is very important to protect one's skin from the sun.
The best way of protecting one's skin from the sun is to keep indoors. This is clearly not practical so if one is spending time outdoors then the best way of protecting the skin is to cover up with UV protective clothing. Wear a hat (especially if one's hair is thinning) and apply sun block to exposed skin. The sun block should be at least a factor 30, easily applied and not too greasy (or it won't be used).