June 2015 | Case of the month

Images

Diagnosis

RevealHide the answer

The diagnosis is consistent with a dermatofibroma.

Introduction

A dermatofibroma is a benign skin lesion. The exact aetiology is uncertain, some believe it to represent a traumatic reaction, such as to an insect bite, others believe it is a true neoplasm. Lesions most commonly affect young adults, with a female predominance.

Clinical features

Distribution
- Commonly on the limbs, especially the thighs and lower legs
- Multiple lesions are common
Morphology
- Most lesions are approximately 5 mm in size and slightly elevated
- Colour tends be red to brown. A deeper area of pigmentation can be found at the periphery of the lesion
- Palpation reveals that much of the lesion sits deep to the skin surface and has a firm consistency
- Pinching the lesion results in central dimpling
- Some lesions are larger and much more nodular in appearance
Dermoscopic appearance
- The appearance of a central scar-like white area associated with a very fine, brown, peripheral pigment network is very characteristic. The holes formed by the network tend to be more rounded as opposed to the shapes seen in melanocytic lesions, which are more angulated
- Early / flat lesions may have little in the way of a central white area

Management

Dermatofibroma do not normally require treatment
Lesions are occasionally removed in cases of diagnostic uncertainty, and in some patients who request removal as a result of the lesion feeling uncomfortable
Treatment is by surgical excision - all specimens must be sent for histology

For more information and images please refer to the clinical chapter on Dermatofibroma.

Latest Cases of the Month

September 2021 - Case of the Month

A 24-year-old woman presented with a several year history of evolving 'lumps' especially on the central chest. The lady had mild facial acne and was otherwise well. 

August 2021 - Case of the Month

A 52 year old man presented with a one year history of skin lesions predominantly on his hands, ears and scalp. He was also complaining of painful swollen fingers associated with morning stiffness. There was no family history of skin or joint problem...