 Skin Cancer Screening
All about skin cancer
Skin cancer in Australia
Each year, over 374,000 Australians are diagnosed with non-melanoma skin cancer and almost 360 Australians die. Over 8,800 Australians are diagnosed with melanoma, and almost 1000 people die. Relative five-year survival rates for melanoma are 90% for Australian males and 95% for Australian women. Survival rates have risen significantly since the early eighties as a result of skin cancers being detected earlier and improved treatment.
Skin cancer prevention and sun protection are key activities of The Cancer Council Australia and its members, and we are committed to reducing harm and deaths by way of public education and information, research, policy and program development, and providing quality and cost-effective sun protection merchandise.
The Cancer Council Australia has made significant achievements throughout Australia in raising awareness of the seriousness of skin cancer and the importance of sun protection. Fewer people consider tanning to be desirable or attractive (and they know the risks) and more people are using sun protection such as sunscreen and hats whenever they are exposed to the sun.
The Cancer Council Australia member organisations have implemented a number of highly successful skin cancer prevention programs over the past 21 years. Evaluations of our skin cancer control programs have found a high level of public awareness of skin cancer prevention campaigns and the need for sun protection. Significant positive changes in both sun-related behaviours and attitudes have been noted since the start of our programs in 1981. Our survival rates are generally higher than in other countries because we are now more aware of the signs of skin cancer, and are detecting them earlier.
Facts and statistics
Skin cancers account for around 80% of all new cancers diagnosed each year in Australia.
Over 382,000 people are treated for non-melanoma skin cancer and melanoma each year in Australia, and over 1300 die. Every year, doctors remove around 720,000 lesions from the skins of Australians because they are suspected skin cancers.
Australian survival rates from melanoma are generally higher than in other countries because we are now more aware of the signs of skin cancer, and are detecting them earlier.
Everyone, regardless of skin colour, is at risk of skin cancer. In Australia, sunburn can occur in as little as 15 minutes on a fine Janurary day. (Roy et al, Health Effects of Ozone Layer Depletion: 1989)
There are three main types of skin cancer: basal cell carcinoma and squamous cell carcinoma, also known as non-melanoma skin cancers, and melanoma. Non-melanoma skin cancer is the most frequently occurring cancer in Australia (over 374,000 new cases each year), but the least life-threatening, although some cases can be fatal.
Melanoma, the most dangerous type of skin cancer, is the most common cancer in people aged 15 to 44 years. Overall, it is the third most common cancer in women, and the fourth most common in men.
Apply adequate amounts of broad-spectrum sunscreen 20 minutes before going outdoors to give protective elements time to bond to your skin (Diffey, Br Med Journ: 1996).
Most Australians apply too little sunscreen. This results in sunscreen users achieving an SPF of between 50-80% less than that specified on the product label (Stokes et al, Photodermatol Photoimmunol Photomed: 1997)
People should apply 2mg sunscreen to each centimetre2 of exposed skin. This equates to approximately a teaspoon for every limb, more for the body (Stokes et al, Photodermatol Photoimmunol Photomed: 1997).
Survival rates have risen significantly since the early eighties as a result of early detection. This is as a result of public education campaigns about skin cancer and increasing community awareness of the damaging effects of UV light. But, skin cancer is still the most common cancer in young people.
Consult your doctor if you have any new skin spots, or a spot that has changed in size, colour or shape. Relative five-year survival rates for melanoma are 90% for Australian males and 95% for Australian women. The earlier a suspected skin cancer is reported to your doctor, the more likely treatment will be successful.
To reduce your risk of skin cancer, The Cancer Council Australia recommends you use all of the following sun protection measures:
- avoid the sun in the middle of the day,
- wear a wide brimmed hat and clothing to cover exposed skin,
- use SPF30+ sunscreen to protect skin that can't be protected with clothing,
- wear close-fitting sunglasses to protect against eye damage, and
- stay in the shade whenever possible.
For more information about skin cancer, telephone our national Cancer Helpline: 13 11 20 or talk to your GP or Dermatologist.
References: Unless otherwise stated, from:
- Australian Institute of Health and Welfare and Australasian Association of Cancer Registries, Cancer in Australia 2001, Canberra, 2004.
- National Cancer Control Initiative, The 2002 National Non-melanoma Skin Cancer Survey, Melbourne, 2003.
Types of skin cancer
There are three main types of skin cancer: basal cell carcinoma and squamous cell carcinoma, known as non-melanocytic skin cancers, and melanoma.
Melanomas start in the pigment cells (melanocytes) while basal and squamous cell carcinomas develop from the epidermal cells.
Basal cell carcinoma (BCC)
- Most common and least dangerous skin cancer
- Appears as a lump or scaling area
- Red, pale or pearly in colour
- As it grows it may become ulcerated like an unhealing sore or one that heals then breaks down again
- Grows slowly, usually on the head, neck and upper torso
Squamous cell carcinoma (SCC)
- Not as dangerous as melanoma but may spread to other parts of the body if not treated
- A thickened red, scaly spot. Later it may bleed easily or ulcerate
- Appears on sites most often exposed to the sun
- Grows over some months
Melanoma
- The deadliest form of skin cancer
- If untreated, cancer cells spread quickly to other parts of the body and form secondary cancers
- Appears as a new spot, or an existing spot, freckle or mole that changes colour, size or shape
- Usually has an irregular or smudgy outline and is more than one colour
- Grows over weeks to months, anywhere on the body (not just in places that get a lot of sun)
What causes skin cancer?
Skin cancer is a disease of the body's skin cells caused by overexposure to ultraviolet (UV) radiation - from the sun's rays or from other sources such as solariums or sunbeds. UV damages the cells' genes.
Most cases of skin cancer in Australians are the result of too much sun exposure when we were children.
While sunburn is linked to melanoma (the most deadly form of skin cancer), regular sun exposure that doesn't result in burning still causes skin damage and increases your risk of other types of skin cancer. There is evidence that UV radiation causes cancer through a cumulative process - the more your skin is exposed to the sun, even without burning, the greater your risk of skin cancer. A suntan is a sign that your skin has been exposed to too much UV radiation and further exposure puts you at increased risk of skin cancer.
More than 5 million Australians get sunburnt each summer, despite well-known sun protection campaigns like Slip! Slop! Slap! running for 22 years.
Most people who get sunburnt do so when the temperature is between 18 and 27 degrees due to the misunderstanding that UV is not so strong on a cool day (Hill et al, Prev Med:1992). It is the UV radiation, which cannot be felt (it doesn't create the heat you feel in the sun) or seen, that causes skin cancer. UV rays can penetrate clouds, so it is possible to burn even on overcast days.
The percentage of people who get sunburnt is higher when people are engaged in any kind of water sports or activities, particularly at the beach or a pool. However, in terms of numbers, most people get sunburnt when relaxing at home or involved in passive recreation.
Early detection and treatment
As skin cancers are visible, they can be seen and checked as soon as they develop. Early detection is crucial if skin cancer is to be cured. Over 90% of all people diagnosed and treated for melanoma survive five years, a sign of successful treatment. Checking your skin regularly will help you detect any changes and potential skin cancers and have them treated promptly. Adult Australian's who have not previously been diagnosed with skin cancer should examine their skin regularly for suspicious spots (Australasian College of Dermatologists: 2002).
The signs to look for are:
- A crusty, non-healing sore.
- A small lump which is red, pale or pearly in colour.
- A new spot, freckle or mole changing in colour, thickness or shape over a period of several weeks to months. Particular attention should be paid to spots that are dark brown to black, red or blue-black.
- If you notice any suspicious spot or change you should consult your doctor immediately.
If your doctor suspects a skin cancer, he/she may perform a biopsy (remove a small sample of tissue for examination under a microscope) or refer you to a specialist.
A variety of methods are available to treat the common skin cancers. Your doctor will choose your treatment by taking into consideration a number of factors. These will include the type of skin cancer, its size and position on your body and your personal preference.
Surgery can be used to remove the skin cancer and a small area of normal skin. This is quite simple and can usually be done under local anaesthetic.
Common skin cancers can be briefly frozen with liquid nitrogen. This is called cryotherapy. Following cryotherapy the skin can become intensely red and peel away. Healing will begin in about a week.
Another technique is simply scraping off small common cancers (curettage) and burning the spot (cautery). Radiation therapy is another option although less commonly used now. It can cause a skin reaction similar to that seen after cryotherapy. Surgery is the method of treatment for melanoma. Very thin melanomas are usually removed along with a small area of normal skin, under local anaesthetic.
For deeper melanomas a wide area of skin may need to be removed to make sure that all the cancer cells have been taken out. The local lymph glands may also be removed at this time.
For more detailed information about treatment of skin cancer, telephone our Cancer Helpline: 13 11 20 or talk to your GP or Dermatologist.
The truth about tanning and solariums
A tan is not a sign of good health or wellbeing. It is a sign of exposure to enough UV to damage the skin.
A natural tan offers limited sunburn protection; usually an average of an SPF4, depending on skin type. A solarium tan (after exposure to predominately UVA) offers even less protection against sunburn or skin damage (Gange et al, J Invest Dermatol: 1985 and Devgun et al, British J Derm: 1982).
Tanning without burning may cause DNA and skin damage leading to premature ageing and potentially, skin cancer (Raab, J Int Med Res: 1990)
Deliberate exposure to sunlight does not provide any health benefits. Australians receive more than sufficient sunlight for vitamin D production from just sitting near a window or by as little as two minutes outside during the day.
A solarium tan is NOT a safe tan. Solariums can emit levels of UV radiation up to five times as strong as the summer midday sun (Standards Australia, Solaria for Cosmetic Purposes: 2002). A solarium tan is induced through concentrated exposure to high levels of UV light. All forms of UV light contribute to skin cancer and cause premature ageing of the skin. A majority of the visible signs of ageing are the result of damage to the skin caused by exposure to UV (Leyden, Br J Dermatol: 1990). Solariums that advertise 'mini' or 'high performance' tans that colour your skin in less than 10 minutes do this by exposing you to extreme levels of UV radiation. You are not reducing your risk of skin cancer by being in the solarium for a shorter period of time.
While the tan fades, the damage to your skin remains. Accumulated exposure to UV radiation (from the sun or solarium) can cause skin damage and premature ageing. This may be evident as loss of elasticity, sagging, yellowish discolouration and brown patches. Sun exposure depletes natural collagen levels in the skin, causing wrinkling and loss of skin definition.
All about UV
The sun gives off many different types of radiation. As well as visible light or sunlight, there is invisible radiation known as ultraviolet radiation. Overexposure to ultraviolet radiation (UVR) from the sun causes skin and eye damage.
There are three main types of UVR, however only UVA and UVB reach the earth's surface. UVB is the most damaging of the two and is responsible for sunburn, suntan, skin ageing, skin cancer and eye damage. UVA also causes skin and eye damage and increases your risk of developing both common skin cancer and melanoma.
Ultraviolet radiation cannot be seen or felt. The heat of the sun comes from the infrared rays of the electromagnetic spectrum and these rays are not responsible for sunburn. Most people get sunburnt when the temperature is between 18-27 degrees due to the misunderstanding that UV is not so strong on a cool day (Hill et al, Prev Med: 1992).
What affects UVR?
The amount of UVR varies through the year and through the day. The higher the level of UVR in sunlight, the more damaging it is. The amount of UVR is greatest when the sun is directly overhead and the distance the sun's rays need to travel to reach the earth is shortest ie in the middle of the day and particularly in the summer months. Levels of UV can be 10 times higher in summer than in winter.
UV levels vary from day to day. On a cloud-free day, maximum UV levels occur when the sun is overhead at solar noon (about 1pm daylight saving time). The danger period for UV is from 10am to 3pm or 11am to 4pm daylight saving time. Seventy per cent of the harmful UVB radiation that is received each day occurs within three hours either side of noon. You can still burn outside these hours, it just takes longer.
UVR can be scattered by cloud (so you can still burn on an overcast day) or reflected from surfaces. You receive as much scattered UV from the sky as you receive directly from the sun.
Fresh snow reflects the greatest amount of UV, but sand, white paint, light coloured concrete and, to a lesser extent, water and some soil, also reflect a significant amount.
UV levels do not rise or fall in accordance with temperature. For example, a cold front that causes a sudden drop in temperature will have no effect on UV unless there is also substantial cloud accompanying the change. The maximum daily temperature usually occurs in the late afternoon. UV, however, is at a maximum when the sun is at its peak overhead - about midday or 1pm daylight savings time. UV intensity is much greater high on a mountain slope than at sea level, because the thinner atmosphere filters out much less of the UV.
Ozone depletion
Ozone is a gas that is part of the earth's upper atmosphere. It plays a vital role in the absorption of UVR, protecting us from up to 90 per cent of the sun's UV rays. The amount of ozone in the atmosphere varies according to geographic location and season.
In the mid 1980s concern over the ozone layer led to the discovery that there had been ozone thinning over Antarctica. This thinning is often referred to as the ozone "hole". The thinning varies with the seasons but it is most noticeable during spring when the amount of ozone drops rapidly. It is known that the impact a thinning ozone layer has a dramatic effect on skin cancer rates as studies from South America show.
The UV Index
The Bureau of Meteorology in conjunction with The Cancer Council Australia has updated its website to provide Australians with improved daily ultraviolet (UV) radiation forecasts and information. Designed in response to increasing public demand for information about UV ratings, the site features an easy-to-read map and informative graphs illustrating how UV levels rise and fall according to the time of day. This feature gives site visitors an idea of when and for how long they should use sun protection while outdoors. Graphical forecasts for each capital city and Alice Springs can be accessed through the Bureau's website. For more information about UV radiation visit the Australian Radiation Protection and Nuclear Safety Agency.
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