Skin cancer - what you need to know
Skin cancer, one of the most common forms of cancer in the Ireland, can be divided into two types: melanoma and non-melanoma.
Melanoma (malignant melanoma) is a type of skin cancer that develops from melanocytes. Non-melanoma cancers (which are about 20 times more common than melanomas) are further divided into two main types: basal cell carcinoma (BCC), which develops from basal cells, and squamous cell carcinoma (SCC), which develops from cells known as keratinocytes.
BASAL CELL CARCINOMA (BCC)
This is the most common form of skin cancer, occurring mainly in white and fair-skinned people, especially those over the age of 75 years. These cancers typically develop on sun-exposed areas of the skin such as the head and neck. The first sign of a BCC is often a small red, pink or pearly lump which appears on previously normal skin. Although the lump is often dome-shaped, BCCs can vary in shape and colour. They usually grow very slowly and it can take many months for one to grow to a centimetre or more. In time, the lump on the skin may crust over, ulcerate or bleed. A skin ulcer caused by a BCC is sometimes called a rodent ulcer which often looks like a small inflamed crater with a raised edge.
BCCs very rarely spread (metastasise) to other parts of the body. However, untreated, they will continue to grow locally and can cause damage to nearby structures. For example, a BCC on the face may erode and damage the nose or ear.
SQUAMOUS CELL CARCINOMA (SCC)
This is the second most common form of skin cancer and usually occurs in white and fair-skinned people. Like BCC's, SCC's are more common in older people and typically develops on the face - most commonly on or around the ears or lips. However, any area of skin can be affected.
They typically start as a small, crusted or scaly area on the skin and may grow into a lump which may look like a wart. A SCC may ulcerate or bleed from time to time. As a SCC grows larger and deeper, it damages nearby structures. For example, if left untreated, an SCC next to a nose or ear can grow into, erode, and then completely destroy the nose or ear.
An SCC may also spread (metastasise) to other areas of the body. However, this is uncommon in the early stages and most SCCs are treated before any spread occurs.
MELANOMA (MALIGNANT MELANOMA)
Melanomas are the least common form of skin cancer. They are, however, the most serious form as they are the most likely form to spread to other parts of the body. Melanoma is twice as common in young women as it is in young men. A typical melanoma usually starts as a small dark patch on the skin (similar to a mole). It can develop from a normal part of skin, or from an existing mole.
WHAT CAUSES SKIN CANCER?
Most skin cancers are caused by sun damage to the skin. About 9 in 10 non-melanoma skin cancers, and about 6 in 10 melanomas are thought to be caused by excessive exposure to the sun. In particular, past episodes of sunburn significantly increase the risk of developing skin cancer. Although skin cancer is rare in children, the amount of sun exposure during childhood is thought to increase the risk of developing skin cancer in adult life. Therefore, it is vital to protect children from the sun.
TREATMENT AND OUTLOOK FOR SKIN CANCER
All three main types of skin cancer - BCC, SCC and melanomas - are curable if they are detected at an early stage. A small operation or other method to remove the affected area of skin is all that is usually required in early cases.
For non-melanoma skin cancers, the overall cure rate is over 95%, even for ones which have been present for a long period of time. The larger they grow, however, the more difficult they are to treat. More extensive surgery or other localised treatments may be needed if they grow large or deep before they are treated.
With melanomas the risk of spread to other parts of the body is high. This is why urgent, early treatment is vital. An operation is usually required to remove the melanoma. Treatments such as chemotherapy, radiotherapy or immunotherapy may be used for melanomas which have spread.
CHECKING FOR EARLY SIGNS OF SKIN CANCER
Try to get to know your skin and familiarise yourself with the look of the normal moles or marks on your body, so that you will recognise any changes which may develop down the line, at an early stage. If you notice any change in the size, shape or colour of an existing mole, or if it starts to bleed or become itchy, or if a new dark area of skin develops then see your GP.
For further information visit www.cancer.ie or www.irishskinfoundation.ie