Seborrhoeic warts

A seborrhoeic wart - properly a seborrhoeic keratosis, and sometimes called a senile wart or a basal cell papilloma - is a common benign growth that appears from middle age onwards.

Despite the name, it is not a wart. It has nothing to do with the human papillomavirus, and it is not contagious. It is an overgrowth of cells in the outer layer of the skin.

What they look like

• Raised, with a rough, warty or waxy surface
• Colour ranging from pale tan to dark brown or nearly black
• A distinctive "stuck-on" appearance, as though the lesion were sitting on the skin rather than growing from it
• Sharply defined edges
• Sometimes with visible small plugs or pits on the surface
• A few millimetres to several centimetres
• Commonly on the chest, back, shoulders, face, scalp and neck

Most people who have one have several, and they accumulate with age. They are not caused by sun exposure in the way that solar keratoses are, though sun-exposed sites are common.

The important distinction

A dark, irregular seborrhoeic keratosis can look very like a melanoma - and a melanoma can look very like a seborrhoeic keratosis. That resemblance is the reason these lesions are examined by a practitioner rather than treated on assumption.

If there is any doubt, the lesion is excised whole and sent to pathology rather than lasered, frozen or burned off, because destructive methods leave nothing to test. See skin cancers.

Have a lesion checked promptly if it is growing quickly, changing colour, becoming irregular, inflamed, bleeding without being knocked, or if it simply looks different from your others. A sudden crop of many new seborrhoeic keratoses is also worth mentioning to your doctor.

Why people have them removed

• They catch on clothing, straps or jewellery, and become irritated or bleed
• They itch
• They are in a shaving area
• Appearance, particularly on the face

There is no medical need to remove a seborrhoeic keratosis that has been assessed as benign and is not bothering you.

How they are removed

Under local anaesthetic where needed, at our Malvern East clinic.

Curettage

The lesion is scraped from the surface with a curette. Because seborrhoeic keratoses sit in the outer layer of skin, this often removes them cleanly and the scraped tissue can still be sent for examination. See curettage.

Cryotherapy

Liquid nitrogen freezes the lesion, which crusts and falls off over one to three weeks. Quick, but leaves nothing to test and carries a higher risk of a pale mark. Used only for lesions assessed as clearly benign. See cryotherapy.

Radiofrequency (electrosurgery)

Removal using high-frequency energy, which also seals small vessels. See electrosurgery.

Surgical excision

Where the diagnosis is uncertain, so the whole lesion goes to pathology. See surgical excision.

Aftercare

• Keep the site clean; follow the dressing instructions given
• Do not pick the scab - let it separate on its own
• Protect the area from sun while it heals, then use sunscreen
• Contact us if there is increasing redness, swelling, pain or discharge

Most sites heal within one to three weeks, depending on the method and the size of the lesion.

What results are realistic

The treated lesion is removed. A flat pale or pink patch commonly remains at the site for some months, and on darker skin a lighter mark can be permanent.

Removal does not prevent new seborrhoeic keratoses forming elsewhere - they continue to appear with age. Individual results vary.

Risks

• Hypo-pigmentation - a pale mark at the site, which can be permanent, particularly after cryotherapy and on darker skin
• Hyper-pigmentation
• Scarring
• Infection
• Bleeding
• Delayed healing
• Incomplete removal and recurrence at the site
• New lesions elsewhere over time
• Missed diagnosis where a lesion is destroyed rather than examined

See risks and complications.

Cost

Cost depends on the number of lesions, their size and the method. As at September 2024 and including GST, a consultation with a Cosmetic Doctor is $150. Removal for cosmetic reasons is not covered by Medicare; removal where medically indicated may attract a rebate.

Booking

Me Clinic, 4 Burke Road, Malvern East VIC 3145. Phone 1300 852 050 or (03) 9569 3511, or use the online consultation form.

Related: skin lesions, skin tags, mole removal, all skin conditions.

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.