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Dermatofibromas

(Benign Fibrous Histiocytomas)

ByDenise M. Aaron, MD, Dartmouth Geisel School of Medicine
Reviewed/Revised Modified Aug 2025
v28368659
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Dermatofibromas are small red-to-brown bumps that result from an accumulation of collagen, which is a protein made by the cells (fibroblasts) that populate the soft tissue under the skin.

Topic Resources

(See also Overview of Skin Growths.)

Dermatofibromas are common among adults, more so in women, and usually appear as single firm bumps, often on the thighs or legs. The bumps are usually less than half an inch (less than about 1 centimeter) in diameter. Some people develop many dermatofibromas.

These harmless bumps are caused by a certain gene.

Dermatofibromas are harmless and usually do not cause any symptoms, except for possible itching or ulceration (sores) after minor injuries.

Usually, dermatofibromas are not treated unless they become bothersome or enlarge. A doctor can surgically remove them if needed.

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