Canadians facing skin cancer epidemic

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This year, there will be 30 per cent more new cases of skin cancer expected in Canada compared to just ten years ago, prompting dermatologists to urge Canadians to practice sun safety to combat this largely preventable disease.

An estimated 76,000 new cases of common skin cancers are expected this year compared to 58,500 new cases for 1994.

The 16th National Sun Awareness Week, organized by the Canadian Dermatology Association (May 31 to June 6, 2004) focused on these common skin cancers, the increasing number of cases, early detection and prevention. Dermatologists in major cities conducted skin cancer screenings for the public.

“The reason we are seeing the number of new cases jump is that people are outdoors unprotected a lot whether they are involved in their usual activities, sports activities or at the beach. Year after year, this results in excessive sun exposure,” says Dr. Joel Claveau, national director of the Canadian Dermatology Association’s National Sun Awareness Program.

“The number of people diagnosed with skin cancer this year will be enough to fill four ice hockey arenas. Surgical treatment is painful and too often disfiguring, to say nothing of the significant costs to the healthcare system.”

Heather Logan, director, Cancer Control Policy with the Canadian Cancer Society, says there are simple measures people can take to protect themselves from the sun. “We recommend reducing sun exposure between 11 a.m. and 4 p.m. as the sun’s rays are strongest between these hours. Try to stay in the shade as much as possible, wear a wide-brimmed hat, and cover your arms and legs with clothing. Also apply a sunscreen with an SPF of 15 or higher.”

Dr. Claveau says people should also use four to five times more sunscreen as not enough is used to achieve the stated SPF (sun protection factor).

He also says that when detected at an early stage, common skin cancers are highly curable. This year, the Canadian Dermatology Association has new information on solar (actinic) keratoses, very common skin lesions which increase the risk of all skin cancers, and squamous cell carcinoma, a common, aggressive form of the disease to help people become aware of their risk for the disease and know the early signs of skin cancer. For further information, the public can visit www.dermatology.ca.

Facts about sun exposure The single major preventable cause of dermatologic diseases is overexposure to the sun.Ê The Canadian Dermatology Association’s Sun Awareness program provides information to the public about how to prevent sun damage and diseases.

Ultraviolet Radiation Exposure to solar and artificial ultraviolet radiation (UVR) is widely recognized as an important and preventable cause of skin cancer.1

The main source of UVR in the environment is the sun. According to Statistics Canada 1996 National Survey on Sun Exposure and Protective Behaviours, Canada’s youth is at particular risk, due to their high levels of sun exposure and low levels of protective behaviours.2 Additionally, the study notes that young adults account for a disproportionate number of outdoor workers,2 such as lifeguards, tree planters, student painters, camp counselors etc., and therefore, may be overexposed to UVR, particularly during spring and summer.

According to the CDA, ultraviolet light works in many different ways to cause skin cancer. Each time skin is exposed to sun and becomes tanned or burned, damage is done to individual cells and to DNA. Some cells die and some repair themselves by getting rid of the damaged DNA. Cells that cannot repair themselves, eventually become defective cells. UVR lowers the body’s immune system, and this makes it difficult to destroy defective cells. Defective cells that are not destroyed slowly grow and produce a tumour.

There are three types of UV sun rays:

  • UVA rays, while not as powerful as UVB, penetrate more deeply into the skin and are responsible for contributing to photodamage and wrinkling of the skin, premature aging, and skin cancer. UVA is prevalent in tanning parlours where tanning devices can emit two to five times more UVA than is found in natural sunlight.
  • UVB rays are shorter but stronger than UVA. UVB primarily affects the skin’s outer layers and is thought to be the primary cause of sunburn, skin aging and skin cancer. UVB rays tend to be more intense during the summer months, at higher altitudes, and at locales closer to the equator. Repeated exposure to UVB over the course of one’s life can cause skin cancer and alter the immune system.
  • UVC rays are the strongest, most dangerous rays. However, little attention is given to UVC rays as they are normally filtered by the ozone layer and do not reach the Earth.

Prevention The goal of the CDA is not to stifle the desire of young people to participate in outdoor sports and activities, but rather to offer some suggestions on how they can still protect themselves from the sun while they’re outdoors. Sunscreen is certainly an important precaution to take, but it’s not enough. The CDA makes the following recommendations to help reduce the risk of long term sun damage to the skin:

Try to reduce sun exposure between 11 a.m. and 4 p.m. (e.g., schedule outdoor sporting events for early evening; if you’re a jogger, plan to do so first thing in the morning)

Seek shade or create your own shade (e.g., choose outdoor cafés with umbrellas or covered porches)

Wear clothing to cover your arms and legs

Wear a wide brimmed hat and wrap-around sunglasses with UVA and UVB protection

Apply sunscreen with minimum SPF #15 or higher with UVA and UVB protection (higher for individuals spending extended periods of time out of doors).

It is important to be familiar with one’s skin. The CDA recommends monthly self-exams of moles and freckles so that individuals can track any changes in their skin. It is important to see a dermatologist if any growth, mole or discolouration appears suddenly or begins to change, or if a sore does not heal. Once cancer develops early, detection and treatment are the best defense.

Certain medications such as antibiotics and retinoids, commonly taken to fight acne, increase the risk of sunburn. Extra sun safety precautions should be taken by individuals on such prescriptions. Alcohol-based sunscreens may also be preferred as they are less likely to cause breakouts.

Young women who are pregnant or taking the birth control pill should also be particularly wary of the sun, as unprotected exposure can sometimes cause darker pigmentation on the cheeks and forehead (also known as the “pregnancy mask”). A sunscreen with an SPF #30 with UVA and UVB protection should definitely be worn.

While the CDA promotes untanned skin as a standard for physical attractiveness, for those who still feel they must have a tan, the CDA recommends the use of self-tanning creams, applied at night, and followed with an SPF #15 or more with UVA and UVB protection sunscreen each day. Self-tanning creams do not provide sun protection.

The CDA strongly recommends that Canadians make it a daily habit to check the UV index, available on various radio stations, http://www.theweathernetwork.com/index_can.htm, as well as Environment Canada’s website: www.ec.gc.ca/, among other locations. The UV index actually tends to peak in May and June on bright days. When the temperature is relatively low, most people don’t think about the potential for sunburns, as they are not hot.

The CDA logo on a sunscreen indicates that the product has been tested and fulfills the criteria of a safe sunscreen as defined by the organization.

As suggested by the CDA, practicing safe sun precautions needs to become as essential to youth as practicing safe sex and responsible drinking – to ensure future health.

Notes
1.1999 The Federal Provincial Territorial Radiation Protection Committee (FPTRPC)
2.Statistics Canada. 1996 National Survey on Sun Exposure and Protective Behaviours.
3.Canadian Cancer Society web site 25.05.2000
Submitted by the Canadian Dermatology Association.