Causes of skin cancer
The greatest risk factor for the 3 main forms of skin cancer is overexposure to ultraviolet (UV) radiation. The most important source of UV radiation is the sun. Exposure to artificial sources of UV radiation is mainly through the use of tanning equipment. It is also possible to be exposed to non-solar sources of UV radiation as a part of certain medical treatments or at work (for example, welding arcs).
UV radiation causes about 90% of melanoma cases.
Know your risks
Visit My CancerIQ (Cancer Care Ontario) in order to determine your risks of developing skin cancer.
Anyone can get skin cancer, but you have a greater risk if you have:
- fair, sun-sensitive skin that burns rather than tans
- red or blond hair
- many moles
- moles which are large or unusual in colour or shape
- a close family history of skin cancer or a personal history of skin cancer
- had excessive exposure to UV radiation from the sun
- used artificial tanning equipment (sunbeds)
- a history of severe sunburns
People with no risk factors, and those with darker skin, can also get skin cancer.
Check your skin for signs of skin cancer
- 53% of melanomas are found by the patients themselves and another 17% by their family members.
- Checking your skin and starting treatment early can lead to a 90% cure rate.
- A skin self-exam (Canadian Dermatology Association) is simple and takes only 10 or 15 minutes once per month.
When you’re looking for skin changes, think A.B.C.D.E.
- A: asymmetry (one side looks different than the other)
- B: border (the edge is irregular)
- C: colour (there are colour differences in the lesion or spot: brown, black, red, grey, or white)
- D: diameter (the lesion or spot is getting bigger)
- E: evolution (changes in colour, size, shape, or symptoms such as itching, bleeding or tenderness)
Download and print the Canadian Dermatology Association’s Melanoma Skin Cancer Know the Signs, Save a Life poster (PDF) to learn more about skin screening and the A.B.C.D.E.‘s of melanoma.
The best way to detect and prevent melanoma (video)
Watch this short video from Evans Health Lab.
- 1 Canadian Cancer Society’s Advisory Committee on Cancer Statistics. Canadian Cancer Statistics 2014. Special Topic: Skin cancers. Toronto, ON: Canadian Cancer Society; 2014. Retrieved from http://www.cancer.ca/~/media/cancer.ca/CW/cancer%20information/cancer%20101/Canadian%20cancer%20statistics/Canadian-Cancer-Statistics-2014-EN.pdf on July 24, 2020.
- Canadian Cancer Statistics Advisory Committee. Canadian Cancer Statistics 2019. Toronto, ON: Canadian Cancer Society; 2019. Retrieved from https://www.cancer.ca/en/cancer-information/cancer-101/canadian-cancer-statistics/past-editions-canadian-cancer-statistics/?region=on on July 24, 2020.
- Canadian Dermatology Association (2020). Skin Conditions. Retrieved from https://dermatology.ca/public-patients/skin/skin-conditions/ on July 24, 2020.
- Canadian Cancer Society (2020). What is melanoma skin cancer? Retrieved from https://www.cancer.ca/en/cancer-information/cancer-type/skin-melanoma/melanoma/?region=on on July 24, 2020.
- Canadian Cancer Society (2020). What is non-melanoma skin cancer? Retrieved from https://www.cancer.ca/en/cancer-information/cancer-type/skin-non-melanoma/non-melanoma-skin-cancer/?region=on on July 24, 2020.
- Government of Canada (2018). Skin cancer. Retrieved from https://www.canada.ca/en/public-health/services/sun-safety/skin-cancer.html on July 24, 2020.