Dermatofibroma

• Dermatofibroma:

  • Common benign fibrous nodule
  • Usually found on skin of lower legs
• Causes:

  • Unclear but sometimes attributed to minor trauma e.g. insect bite, followed by proliferation of fibroblasts in the dermis causing the lesions
  • Mostly seen in adults
  • Common on lower limbs of women
• Clinical features:

  • Firm hard papule or nodule
  • Size varies from 0.5-1.5ch diameter
  • Overlying skin dimples on pinching the lesions - the dimple or pinch sign
  • Colour may be pink to light brown in white skin and dark brown to black in dark skin
  • Don't usually cause symptoms but are sometimes painful, tender or itchy
• Treatment:

  • Reassurance - if diagnosis is clear then excision should not be undertaken for cosmetic reasons as healing can be poor
  • Excision or biopsy indicated in =
  • Atypical features - growing, ulceration, asymmetrical colours
  • Nuisance
  • Recurrence is common