Dermatofibroma

Question 1

Define dermatofibroma.

Answer 1

A dermatofibroma is a common overgrowth of the fibrous tissue situated in the dermis. It is benign and will not turn into a cancer.

Question 2

What is the aetiology of dermatofibromas? What are the risk factors for dermatofibromas?

Answer 2

Aetiology unclear.

• Minor injury to the skin e.g. prick from a thorn, insect bite
• Women
• 20 to 49 years of age

Question 3

Summarise the epidemiology of dermatofibromas.

Answer 3

Appears in about 3% of derm samples

Asymptomatic so prevelance is unknown

Question 4

What are the signs and symptoms of dermatofibromas?

Answer 4

A firm bump that feels like a small rubbery button lying just under the surface of the skin <1 cm in diameter.

They can vary in colour from purple to pink and can sometimes appear
brown or grey.

A dimple may appear over a dermatofibroma when pinched.

They can appear anywhere but are most common on the lower legs of
young to middle-aged adults, and on the upper arms in females.

Sometimes itchy

Usually asymptomatic

Question 5

What are investigations for dermatofibromas?

Answer 5

CLINICAL DIAGNOSIS

(skin biopsy)

Question 6

What is the management of a dermatofibroma?

Answer 6

Dermatofibromas sometimes disappear without any treatment, although in many cases they can last indefinitely.

Can give treatment but may leave scarring