When should you get a skin check? Dr. An-Wen Chan, dermatologist at Women’s College Hospital, says knowing these five letters can save your life.

Checking your skin is an important part of healthy skin care – no matter your age. General signs of potential skin cancer include lesions that change in size, colour or shape. In addition, some skin cancers might bleed or feel sore. Melanoma, the most serious type of skin cancer, accounts for almost four percent of new cancer cases each year and almost two percent of cancer-related deaths. When examining your skin for melanoma, remember A, B, C, D, E:

A is for Asymmetrical Shape: 

An asymmetrical or irregular shape may be cause for concern. If you draw a line down the middle of your spot, both sides should be the same

B is for Border: 

Non-cancerous moles usually have smooth, even borders, while melanoma lesions may have jagged, irregular borders.

C is for Colour: 

Melanoma lesions can have more than one colour—black, grey and pink—or they may have no pigment at all and just look like a raised, red bump. Regular moles, on the other hand, should be just plain grey or brown.

D is for Diameter: 

Anything greater than six millimeters in diameter—about the size of a pencil eraser—is worth a second look.

E is for Evolution: 

Look out for itching, burning, growth or change in colour. Moles aren't supposed to change.

It's up to you to know what's normal for your own skin and to alert a doctor if something new or different suddenly appears. Major risk factors include those related to amount of lifetime UV exposure (sun exposure, sun burns, tanning bed usage or older age) and sensitivity to sun damage (fair skin or immunosuppression). Bottom line: protect yourself from the sun and check your skin for any of these signs of skin cancer.

Dr. An-Wen Chan is a dermatologist and senior scientist at Women’s College Hospital in Toronto.