Dermatofibroma

What is dermatofibroma ?

• It is a benign condition
• It typically appears in females 9 times more often than in males.
• It is also known as superficial benign fibrous histiocytoma.

What is it caused by ?

• The exact cause of its development is unknown.
• There was an inital theory that it was a reaction following an insect bite. It is also hypothesized to be a neoplastic growth.
• Hypothesis: The female predominance and its occurence in young age suggests that hormonal factors may play a role.

What does it look like ?

• It presents as dermal bumps which are typically present on the legs.
• It displays the dimple sign when compressed laterally: the lesion becomes depressed.
• The nodules can be dark-coloured. This is because of the deposit of hemosiderin. (In those cases, it can mimick malignant melanoma)

  

  Pigmented Dermatofibroma

When examined by a dermatologist with a dermoscopy, the most typical pattern is a stellate white central pattern surrounded by a rim of hyperpigmentation. At the surface, a pigmented network may be present.