Moles are small spots on your skin. Almost everyone has one or more moles, and they are usually not anything to worry about. But when are moles a cause for concern? Let’s look at normal and suspicious moles.

Normal moles

Moles usually appear circular with smooth edges. They can be brown or flat, smooth or rough, and sometimes have hair growing from them. It is normal for babies to be born with moles, for new moles to appear in children, teenagers and young adults, for moles to fade or disappear as you get older, and for your moles to darken during pregnancy.

Suspicious moles

A mole may be suspicious if it shows one or more of the following ABC signs of melanoma. If you notice any of these signs, you should quickly see a doctor for a thorough skin check-up.


The two halves of the mole don’t match if you draw a line through the middle.
Border The edges of the mole are notched or uneven.
Colour There are a variety of colours, including shades of black, blue, red, tan, or white.
Diameter The mole is larger than 6mm (approx. the size of a pencil eraser).
Elevated The mole is raised, nodular, or lumpy to the touch.
Firm The mole feels hard or firm.
Growing The mole has grown bigger in the past few weeks or months.

When to see a doctor about your moles

Outside of your annual skin cancer check, you should see a doctor if any mole:

  • Changes shape, colour, or size
  • Becomes crusted, itchy, flaky, or bleeds easily
  • Won’t heal after a few weeks
  • Becomes raised or irritable; or
  • Appears anew, especially if you are over the age of 30.

What will happen if the doctor thinks the mole is suspicious?

If the doctor examines the mole through dermoscopy and identifies suspicious signs that indicate a malignancy (skin cancer), a biopsy may be performed. The skin tissue sample will be sent to a pathologist to confirm the diagnosis. This diagnosis will determine the treatment approaches available to you, which may include excision or topical creams. Sometimes, the biopsy will take off the whole mole and no further treatment is required.

Can non-malignant moles be removed?

Yes, in most cases your doctor can remove non-cancerous skin lesions for you, but only after they have been carefully checked for signs of malignancy. It can be very dangerous to remove any lesion without first examining it for signs of skin cancer.

How can I prevent my moles from becoming cancerous?

Most skin cancers arise anew, rather than developing within the moles and freckles that have been on your skin since childhood. The majority of skin cancers develop because of unprotected or prolonged exposure to the sun’s ultraviolet (UV) rays, so it’s important to:

  • Always wear sunscreen every day, and re-apply every two hours;
  • Avoid going outside during the middle of the day when UV levels peak;
  • Cover exposed skin with a hat, sunglasses, and sleeves;
  • Stick to the shade whenever possible;
  • Never use a solarium (sun bed or tanning bed);
  • Self-monitor your skin for any new or changing moles in between professional skin checks; and
  • See a doctor once a year for a professional full-body skin cancer check using dermoscopy for a head-to-toe examination of your entire skin surface.