Skin cancer

What is skin cancer?

Skin cancer occurs when skin cells are damaged.

This typically occurs by overexposure to ultraviolet (UV) radiation from the sun. There are three main types of skin cancer: melanoma, basal cell carcinoma, and squamous cell carcinoma.

Skin cancer involves the uncontrolled growth of abnormal cells in the skin. Each time your skin is exposed to ultraviolet (UV) radiation, changes take place in the structure and function of your skin cells. Over time, your skin may become permanently damaged, with every additional decade of overexposure increasing your risk of skin cancer.

All skin types can be damaged by exposure to UV radiation. Even if you have a skin type that is less likely to burn, you are still at risk of developing skin cancer.

Every year in Australia:

• Skin cancers account for approximately 80 per cent of all newly diagnosed cancers
• Between 95 and 99 per cent of skin cancers are caused by exposure to the sun
• GPs have over 1 million patient consultations for skin cancer
• 2,000 people die from skin cancer

Yet, most skin cancers are preventable and the majority can be successfully treated if found early.

The three main types of skin cancer – melanoma, basal cell carcinoma, and squamous cell carcinoma – are named for the type of cell they come from.

Melanoma

Melanoma is the most dangerous form of skin cancer, and can grow quickly – developing over weeks to months. If not treated early, they are prone to spread to other parts of the body.

Common melanomas involve a new spot or existing one that changes colour, size or shape. They are usually flat with an irregular, smudgy outline and are often more than one colour.

Nodular melanoma is a highly dangerous form of melanoma that looks different; they are raised from the start and even in colour (often red or pink, though some are brown or black). This type of melanoma grows quickly and can be life threatening if not detected and removed quickly.

It is important to note that unlike most other skin cancers, melanoma can occur on skin that does not get direct sun exposure e.g. soles of feet, groins/genitals and under finger and toe nails. Careful whole body skin surveillance is needed.

Basal cell carcinoma

The most common type of skin cancer, basal cell carcinoma most often occurs on the head and neck, followed by the upper body. These cancers are often red and slightly raised, with a scaly area that can bleed if knocked. They rarely spread to other parts of the body.

Squamous cell carcinoma

Squamous cell carcinoma grows over a period of weeks or months, and sometimes may spread to other parts of the body if not treated quickly. It occurs most often, but not only, on areas exposed to the sun – the head, neck, hands and forearms. This type of skin cancer looks like thickened, red, scaly spots.

Symptoms of skin cancer

The sooner a skin cancer is identified and treated, the better the chance of avoiding surgery or, in the case of a serious melanoma or other skin cancer, disfigurement or death.

Symptoms include:

• Crusty, non-healing sores
• Small lumps that are red pale or pearly in colour
• New spots, freckles or moles that change in colour, thickness or shape over a period of weeks to months (in particular dark brown to black, red or blue-black)

More information on how to check your skin for signs of skin cancer is provided by the Cancer Council.

Causes of skin cancer

Australia has one of the highest rates of skin cancer in the world. Anyone can develop skin cancer, though the risk increases as you get older. The majority of skin cancers in Australia are caused by exposure to ultraviolet (UV) radiation in sunlight.

Diagnosis and treatment of skin cancer

If you notice any changes in your skin, consult your doctor – they may perform a biopsy (removing a small sample of tissue for examination under a microscope) or refer you to a specialist.

Skin cancers are almost always removed. With more advanced skin cancers, some of the surrounding tissue may also be cut out to make sure all the cancerous cells have been eliminated.

Common skins cancers can be treated with ointments or radiation therapy. They can also be removed with surgery (usually under a local anaesthetic), cryotherapy (using liquid nitrogen to rapidly freeze the cancer off), curettage (scraping) or cautery (burning).

Prevention of skin cancer

The SunSmart UV Alert indicates when ultraviolet (UV) radiation is forecast to be three or above, and provides daily sun protection times as a guide for when you do or don’t need sun protection.

Whenever UV levels reach a level of three and above, a combination of sun protection measures (hats, clothing, sunscreen, shade and sunglasses) are needed. It’s important to remember that UV can still be damaging on cool and cloudy days.

Further information and sources

• Health Direct Australia
• Cancer Council Australia
• SunSmart