Early Skin Exams Reveal Melanoma Before It Spreads

Skin exams for melanoma are a practical way to catch the disease before it spreads, a concern that affects roughly 11,300 Canadians each year.

Why early detection matters

Melanoma accounts for about one in 24 Canadians developing the cancer over a lifetime. When the tumor stays thin, it remains confined to the outer skin layer, but thicker lesions can reach the deepest layer where blood vessels and lymph channels sit, allowing the cancer to travel.

“Thicker melanomas grow into the layers of the skin, so the thicker the melanoma is, the more concerning it is,” said Krista Rubin, a melanoma nurse practitioner at Mass General Brigham. At stage four, survival drops to between 16 % and 32 %, making prevention and early detection critical.

Only 20 % to 30 % of melanomas arise from an existing mole; the majority appear as new growths or changes. This challenges the common belief that all skin cancers develop from pre‑existing spots.

What to look for:

Rubin advises watching for any spot that itches, bleeds, or stays irritated for more than two weeks. “If it’s been two weeks or more, that’s something they need to pay attention to,” she said.

Melanomas can be asymptomatic, showing no irritation or obvious dark coloration. “Some melanomas don’t have any distinguishing characteristics,” Rubin noted, meaning they may look like flesh‑colored bumps rather than the classic dark, irregular spots many expect.

The widely taught ABCDE method remains a useful screening tool. It asks you to assess:

Asymmetry – the two halves don’t match.
Border – uneven or ragged edges.
Color – more than one hue, such as black with red or blue.
Diameter – larger than a pencil eraser (about 6 mm).
Evolution – any growth or change over time.

“If you have a mole that has one or those characteristics or possibly even two, it doesn’t guarantee that it’s a melanoma, but it’s something that you want to pay attention to,” Rubin explained.

Those with a personal or family history of skin cancer may be advised to check more frequently, sometimes monthly, based on individual risk.