Dermatofibroma (syn. histiocytoma)

LAST UPDATED: Jun 05, 2026

Patient Information Leaflet
Link: Dermatofibroma

https://pcds.org.uk/patient-info-leaflets/dermatofibroma

Introduction

A dermatofibroma is a benign skin lesion. The exact aetiology is uncertain, some believe it represents a traumatic reaction, such as to an insect bite; others believe it to be a true neoplasm.

This chapter is set out as follows:

History
Clinical findings
Images
Management

History

Age of presentation - young adults are most commonly affected
Sex - woman more than men
Symptoms - generally asymptomatic although can be painful when knocked
Do not have a malignant potential (dermatofibroma sarcoma protuberans is an unrelated tumour)

Clinical findings

Distribution

Commonly the limbs, especially the thighs and lower legs. The trunk is less commonly affected
Multiple lesions are common

Morphology

Most are approximately 5 mm in size and slightly elevated. Some lesions are larger, more nodular in appearance. Lesions can occasionally be flat or indented, especially on the trunk
There is often a deeper area of pigmentation at the periphery
Palpation is a particularly important aspect of the diagnosis. Lesions should be pinch positive - if you place your thumb and index finger a few mms either side of the visible lesion, press firmly down and then inwards, a regular firm ''rubbery'' lump should be palpable, which is bigger than what can be seen above the skin (as with an iceberg). Pinching may result in central dimpling. To do this test properly can be slightly uncomfortable for patients, who are best informed
There are a number of dermatofibroma variants - the cellular dermatofibroma represents 5% of all dermatofibromas, and is clinically larger than more typical lesions

Dermoscopic features (hover over terminologies for description)

The appearance of central white structures is characteristic of many dermatofibromas. This can be structureless (scar-like) or composed of shiny white structures made up of either lines or a network, best seen in polarised mode. Flatter / depressed lesions tend to have little in the way of a central white area
Lesions tend to have a brown or pink/brown periphery, which may have areas of a fine brown rounded network
Vessels can be dotted (the most common pattern), or fine and radial (pointing to the centre) - for more information on vessels refer to the chapter Vessel patterns in dermoscopy

Beware - when to consider an alternative diagnosis such as melanoma

An atypical history - a dermatofibroma should not arise from a pre-existing ''mole'' or other area of pigmentation
If a lesion is just pink, lacking peripheral pigment, especially if it is pinch/dimple negative. It is important to note that pressure from a dermatoscope onto a pink papule / nodule can blanch the centre making it appear white

Clinical Images

Please refer to notes on image rights at bottom of the page with regards to individual image ownership.

Dermatofibroma - pinch positive If you place…

Dermatofibroma on the shinA subtle rim of brown…

DermatofibromaCopied with kind permission from…

Dermoscopic appearance of previous figureA…

Dermatofibroma on the right upper backCopied with…

DermatofibromaThe shiny appearance is an…

Dermatofibroma

Copied with kind permission…

Dermoscopic appearance of previous figureA white…

Variable central white structures in the three…

Central white structures - best seen in polarised…

Dermoscopic appearance of upper lesion from…

Dermoscopic appearance of previous figure In…

Dermatofibroma in skin of colourA hypopigmented…

Dermatofibroma in skin of colourWhite central…

DermatofibromasCopied with kind permission from…

Dermosocopic image of previous figureCopied with…

Close-up of the previous imageThe green arrows…

A flat dermatofibromaPalpation revealed a firm…

Flat dermatofibromaThe predominant feature is a…

Dermoscopic appearance of previous figureThe…

A flat dermatofibomaClinically pinch/dimple…

Dermatofibroma - 'aneurysmal' in typeThe dotted…

Dermoscopic appearance of previous figureWhite…

Dermatofibroma with sebaceous gland hyperplasia…

DermatofibromaThis represents one of the least…

DermatofibromaAlthough this odd looking…

Dermatofibroma come in different shapes and…

Amelanotic melanomaThis enlarging solitary pink…

Management

Dermatofibroma do not normally require treatment as they are benign lesions with no malignant potential
Other than cases of diagnostic uncertainty, dermatofibromas should not be excised where possible - surgical scars are significant larger than the dermatofibroma, and incomplete excision (lesions are larger under the skin surface) often leads to recurrence

Disclaimer - the author PCDS cannot accept responsibility for any misleading or incorrect statements, and the management of individual patients remains the direct responsibility of the individual doctor. We do however hope that visitors to this site can contact us regarding comments that are considered misleading or incorrect so that we can continue to improve the site.

Image Rights - The PCDS would like to thank Dermatoweb, DermQuest (Galderma), and others who have contributed images. All named individuals and organisations maintain copyright for the relevant images.