Dermatofibromas are firm, red-to-brown, small papules or nodules composed of fibroblastic tissue. They usually occur on the thighs or legs but can occur anywhere.
Dermatofibromas are common among adults, more so in women. Their cause is probably genetic. Lesions are usually 0.5 to 1 cm in diameter, firm, and may dimple inward with gentle pinching. Most lesions are asymptomatic, but some itch or ulcerate after minor trauma.
Diagnosis of Dermatofibromas
Diagnosis of dermatofibromas can often be made clinically. Lesions are sometimes biopsied to exclude melanocytic proliferation (eg, nevus, solar lentigo, melanoma Melanoma Malignant melanoma arises from melanocytes in a pigmented area (eg, skin, mucous membranes, eyes, or central nervous system). Metastasis is correlated with depth of dermal invasion. With spread... read more 
) or other tumors.
