[3] Risk factors for developing multiple dermatofibromas include lupus, HIV, blood cancer and some medicines that weaken immunity.

[3] Dermatofibromas[4] are hard solitary slow-growing papules (rounded bumps) that appear in a variety of colours, usually brownish to tan.

Some physicians and researchers believe dermatofibromas form as a reaction to previous injuries such as insect bites or thorn pricks.

Dermatofibromas are classed as benign skin lesions, meaning they are completely harmless, though they may be confused with a variety of subcutaneous tumours.

[7] Deep penetrating dermatofibromas may be difficult to distinguish, even histologically, from rare malignant fibrohistocytic tumours like dermatofibrosarcoma protuberans.