Dermatofibromas are harmless benign skin growths, found especially on the legs, that range in size from about 0.5 to 1 cm. They are hard, rounded bumps that may appear in a variety of colors, usually brownish to purple. Typical dermatofibromas cause little or no discomfort, although itching and tenderness does occur sometimes. Some physicans and researchers believe they are reactions to previous injuries such as insect bites or thorn pricks, as they are composed mainly of dense scar tissue in the form of collagen.

Dermatofibromas occur most often in women: the male to female ratio is about 1:4. Since it is not known exactly what causes them to appear, there is no known way to prevent them. Most physicians will advocate treatment only if the lesion is in the way of shaving, or is becoming irritated by clothing. Removal can be done surgically, but since much of the growth extends beneath the surface of the skin, the scar may be larger and more noticeable than the original tumor. It is more common to shave off the top of the growth, or to use cryosurgery.

See also

• Dermatology
• Seborrheic keratosis