Seborrhoeic keratosis (age wart): what the term means
Medically reviewed by Dr Sin Yong · Last reviewed · 3 min read
Published 13 October 2026 · Reviewed by Dr Sin Yong
Seborrhoeic keratosis (age wart) is a benign overgrowth of keratinocytes, the skin's outermost cells, seen as a waxy, sharply bordered, tan to dark brown plaque that looks pasted onto the surface. It is not a viral wart, not contagious and does not become cancer, but melanoma and other pigmented skin cancers can mimic it, so dermatoscopic diagnosis comes before any removal by cryotherapy, curettage, electrocautery or ablative laser.
Key facts
ICD-10
L82
What it is
Benign proliferation of keratinocytes, driven by clonal change and age more than by sun alone
Where
Face, scalp, chest, back; anywhere except palms and soles; most adults have at least one by middle age
Removal
Cryotherapy, curettage, electrocautery or ablative laser, chosen by thickness and site once confirmed benign
Illustrative image, not a patient.
Where seborrhoeic keratosis matters on this site
The age wart is referred to across the growth pages because it is the lesion most often brought in as a mole, a wart or a sun spot, and the one that most often needs the dermatoscope to earn its name.
The waxy, stuck-on look reassures the patient; the dermatoscope has to reassure me.— Dr Sin Yong
Seborrhoeic keratosis: age warts: the full condition page, with the lookalikes table and the removal options by thickness and site.
Dr Sin Yong's rule is that any pigmented growth is examined, with the dermatoscope where indicated, before anyone freezes, burns or lasers it.
Not to be confused with
The stuck-on look is reassuring but not diagnostic. Under the dermatoscope, a seborrhoeic keratosis has a recognisable set of features, and the lookalikes have theirs.
Seborrhoeic keratosis itself: a sharply demarcated, waxy plaque. Dermoscopy typically shows multiple milia-like cysts, comedo-like openings, and fissures and ridges that give a brain-like surface, sometimes with hairpin vessels ringed in white. The edge is often described as moth-eaten.
Melanoma: the mimic that matters. Asymmetry, more than one colour, an irregular pigment network, a blue-white veil or irregular dots and streaks are the features that end the stuck-on assumption and lead to biopsy.
Pigmented basal cell carcinoma: pearly, with branching vessels and grey-blue nests, sometimes ulcerated.
Solar lentigo: flat, light brown and uniform, with a fingerprint-like or faint network pattern; a thin keratosis can arise from one.
Viral wart: a rough, papillomatous surface with dotted or thrombosed vessels and interrupted skin lines; see wart removal.
Dermatosis papulosa nigra: the small, dark, smooth papules on the cheeks of darker skin, which are a form of the same lesion and are treated with the same care about pigment change.
A keratosis that is changing, bleeding, irregular or unlike its neighbours is the one that gets examined most closely, because a pigmented skin cancer can wear the same coat.
Where it fits
The one question that matters with an age wart is whether it is definitely benign. The typical lesion is diagnosed by its stuck-on, waxy, sharply bordered look under the dermatoscope; a growth that is changing, bleeding, irregular or unlike its neighbours is examined more closely before anything is destroyed, because a pigmented skin cancer can wear the same coat. Once confirmed, removal is elective and quick, and new lesions can appear over the years because the tendency is largely genetic and age-related. Full page: seborrhoeic keratosis; the flat brown spots it is confused with on sun spots; pigmented growths in general on mole removal.
Another common benign bump, with a different cause and treatment, is milia.
A smooth, bright red dot is more likely a cherry angioma than a keratosis.
How a true mole differs is set out in the glossary.
It is not a viral wart; the difference is defined in the glossary.
Frequently Asked Questions
It should not be. A home freezing kit cannot confirm that the lesion is a seborrhoeic keratosis rather than a melanoma that resembles one, and destroying it removes the evidence. In darker skin, cryotherapy can also leave lasting pigment change, which is one reason laser-based removal is often preferred in Singapore. Diagnosis comes first, then the method is chosen by thickness and site.
Typically a sharply bordered, waxy plaque with milia-like cysts, comedo-like openings and a fissured, brain-like surface, sometimes with hairpin vessels surrounded by a white halo. Those features are reassuring. Asymmetry, several colours, an irregular network or a blue-white veil are not, and a lesion showing them is biopsied rather than treated as an age wart.
No. Despite the name it is not a viral wart and does not spread from person to person or from one site to another. It is an overgrowth of the skin's own surface cells, overwhelmingly a feature of accumulated birthdays.
It should not be. Melanoma and other pigmented skin cancers can mimic one, so Dr Sin Yong confirms the diagnosis with a dermatoscope before any cryotherapy, curettage or laser. Destroying a lesion without a diagnosis removes the evidence.
