A dermatofibroma is a common skin growth. It is a small, firm bump on the skin. The dermis layer of skin contains nerve endings, glands, and vessels. The bump is an overgrowth of the tissue in the dermis layer. The bump is generally pinkish-brown in color. It is often found on the legs. Sometimes more than one appears. Generally, they are harmless and are not connected to skin cancer.
The cause is unknown. Dermatofibromas sometimes appear after a minor injury to the skin. This can include an insect bite or a prick of a thorn.
These bumps rarely cause symptoms. However, it is always important to see a doctor about any new skin growth.
Usually reddish-brown in color
- Are darker in individuals with darker skin
- May change color over time
- Found most often on the legs, but may also appear on the arms or torso of the body
- Small in size (3-10 millimeters)
- Very firm to touch
- Sometimes itchy or sensitive when touched
- Raised from the skin and may bleed if damaged (a dermatofibroma can bleed if shaven over)
Your doctor will ask about your symptoms and medical history. A physical exam will be done.
A dermatofibroma is diagnosed by sight and touch. Your doctor may also squeeze the skin over the bump. When squeezed together, a dimple will form.
If diagnosis is not certain, the bump can be surgically removed. The removed tissue will be examined under a microscope.
Dermatofibromas do not go away by themselves. Treatment is usually not needed. It may be done if it is causing discomfort (itching or pain) or if they are unsightly. They do not pose any health risk.
Treatment options include the following:
The dermatofibroma may be cut off surgically. This can be done with local anesthesia.
Keep in mind that the dermatofibroma is usually deep. The removal will leave a scar.
Liquid nitrogen can be used to freeze the bump and flatten it out. This method usually leaves a white mark behind. The dermatofibroma may also eventually grow back.
- Reviewer: EBSCO Medical Review Board James P. Cornell, MD
- Review Date: 09/2017 -
- Update Date: 11/16/2012 -