Moles and skin tags: a complete guide

Moles and skin tags are extremely common. Most are harmless and need no treatment at all. The point of this guide is to help you tell which is which, know what the warning signs are, and understand what proper removal involves - and what it should never involve.

Surgical warning: Any surgical or invasive procedure carries risks. Before proceeding you should seek a second opinion from an appropriately qualified health practitioner.

What moles are

A mole (naevus) is a benign growth of melanocytes, the pigment-producing cells in the skin. They are usually brown, but can be pink, red, black or skin-coloured, flat or raised, with or without hairs. The Australasian College of Dermatologists notes that Australian children commonly have dozens of moles by their mid-teens.

Types

• Congenital naevi - present at birth or appearing in the first months. Around 1 in 100 newborns has one. Large congenital naevi carry a higher lifetime melanoma risk and should be monitored by a doctor.
• Acquired (common) naevi - the ones that appear through childhood and early adulthood, influenced by genetics and sun exposure. Most people have between 10 and 40.
• Dysplastic (atypical) naevi - larger, irregular in outline and uneven in colour. They often run in families. Having many of them raises melanoma risk, and any change in one warrants prompt assessment.

New moles appearing after about age 40 are less usual and are worth having looked at.

The warning signs: ABCDE

Australia has among the highest melanoma rates in the world, and outcomes depend heavily on how early it is found. Check your own skin regularly and ask someone to check your back and scalp.

• A - Asymmetry. One half does not match the other
• B - Border. Irregular, notched, scalloped or blurred edges
• C - Colour. More than one colour, or uneven distribution of colour
• D - Diameter. Larger than about 6mm - though melanomas can be smaller
• E - Evolving. Any change in size, shape, colour or elevation, or new itching, bleeding or crusting

Two additions worth knowing:

• The ugly duckling. Most of your moles resemble each other. The one that looks different from the rest deserves a look, even if it passes ABCDE.
• Amelanotic melanoma. Some melanomas have little or no pigment and appear pink, red or skin-coloured. A new, firm, growing lump warrants attention even if it is not brown.

Melanoma can occur anywhere, including under a nail, on the sole of the foot, on the scalp and in genital skin. Check the places you do not normally look.

If anything on your skin is changing, see your GP. That is the fastest route to assessment and, if needed, a dermatologist referral.

What skin tags are

Skin tags (acrochordons) are small, soft, skin-coloured growths that hang on a narrow stalk. They are benign, not contagious, and not a sign of infection. They form where skin rubs - neck, armpits, groin, under the breasts, eyelids and thighs - and are made of loose collagen fibres and small blood vessels under a layer of skin.

They are more common with age, in pregnancy (hormonal change), and in people carrying more weight. Numerous skin tags can be associated with insulin resistance, so if a lot appear together it is reasonable to mention it to your GP.

Skin tags are not the same as warts - warts are rough, caused by a virus, and can spread. Anything you are unsure about should be looked at rather than guessed at.

Removal, and the rule that governs it

A pigmented lesion that has not been assessed must not be lasered, frozen or burned off. Destructive methods leave nothing to send to pathology and can erase the surface evidence of an early melanoma while the deeper part remains. Anything with any question over it is excised whole and tested.

Assessment first. Then:

• Surgical excision - the lesion is removed in full under local anaesthetic, closed with sutures, and sent for pathology. The method for anything suspicious or changing. Leaves a linear scar.
• Radiofrequency shave - a fine handpiece removes a raised, clearly benign lesion level with the skin and seals the base. Suitable for skin tags and raised benign naevi; tissue can still be sent for pathology. Because it removes only what is above the surface, pigment can return.
• Cryotherapy - liquid nitrogen, appropriate for confidently diagnosed benign lesions such as skin tags, seborrhoeic keratoses and solar keratoses. Not used on pigmented moles. Often leaves a pale mark, particularly on darker skin.
• Snip excision - small scissors under local anaesthetic, commonly used for skin tags.

Full detail: how to remove a mole.

Risks of removal

Bleeding - more likely on blood thinners. Infection, which is the main risk once the skin is open; follow the wound care instructions. Scarring, which is permanent, though usually small. Recurrence: a shaved naevus can regrow pigment, and a skin tag can form again where skin continues to rub. Any pigment returning at the site of a previous removal should be assessed promptly - it is usually benign regrowth, but it can look like, and occasionally be, something more serious, which is why it is never assumed.

Do not remove them at home

Nail clippers, scissors, thread, freezing kits, wart preparations, bleaching agents, tea tree oil and apple cider vinegar all carry the same problems: infection, bleeding, chemical burns and unnecessary scarring. And the serious one - if the lesion was not what you assumed, you have destroyed it without a diagnosis. There is no safe way to do this at home.

At Me Clinic

Our doctors assess and remove skin lesions, and anything with any question over it goes to pathology. Me Clinic does not have a dermatologist on staff. Where specialist dermatological assessment, skin cancer management or complex reconstruction is required, we refer you on. Your GP can also refer you directly.

Mole removal consultation $150, skin assessment $50, including GST, as at September 2024. Removal is quoted after assessment. Me Clinic, 4 Burke Road, Malvern East VIC 3145. Phone 1300 852 050 or (03) 9569 3511.

Related: mole removal, skin tags, scarring.

Individual results may vary. Any surgical or invasive procedure carries risks. Before proceeding you should seek a second opinion from an appropriately qualified health practitioner.