What is a cutaneous horn?
A cutaneous horn (cornu cutaneum) is a fairly common horn-like growth on the skin. It is usually an elongated column that rises from a small tumour with a central crater, and can look like the horn of a rhinoceros, for example. The size varies from a few millimetres to a few centimetres. The horn is composed of compact masses of dead skin cells.
Who gets a cutaneous horn?
Cutaneous horns are seen mainly in older people with strongly sun-damaged skin (chronic actinic skin damage). A horn is therefore often found in people who also have actinic keratoses, and when the base of the horn is examined microscopically, the picture of an actinic keratosis is indeed often seen. In some cases a squamous cell carcinoma turns out to lie at the base of the cutaneous horn.
How is it treated?
Because a horn can arise from a squamous cell carcinoma, surgical removal is the preferred method. Deep curettage (scooping out) of the horn including its base is also a good treatment. Your doctor will almost always have the tissue examined microscopically by the pathologist. Because sun damage is the main factor in the development of a cutaneous horn, sun protection is advisable.
When to see a doctor
See your GP or a dermatologist for any horn-like growth on the skin, especially in older or sun-damaged skin, or if the base is red, firm, tender or growing. Because skin cancer can lie beneath a cutaneous horn, it is important to have it removed and examined rather than leaving it or trying to remove it yourself.