From dermoscopedia


DERMATOFIBROMA Introduction Dermatofibromas are prevalent cutaneous lesions that most frequently affect young to middle-aged adults, with a slight predominance in females. Clinically, dermatofibromas appear as firm, single or multiple firm papules/nodules with a relatively smooth surface and predilection for the lower extremities. Characteristically, upon lateral compression of the skin surrounding dermatofibromas, the tumors tend to pucker inward producing a dimple-like depression in the overlying skinThis glossary term has not yet been described.; a feature known as the dimple or Fitzpatrick’s sign.

DermoscopyDermoscopy is a non invasive diagnostic method. criteriameasure of how well one variable or set of variables predicts an outcome: [1]

Typical dermoscopic pattern (Figure 1): [2]

8 5 DF FIGURE 1.jpg
  • Peripheral delicate pigment networkGrid-like pattern consisting of interconnecting pigmented lines surrounding hypopigmented holes.: light-to-medium pigment network, brown in colorColor (American English) or colour (Commonwealth English) is the characteristic of human visual perception described through color categories, with names such as red, yellow, purple, or blue., with a fine and delicate quality, which gradually fades into the surrounding skin
  • A central scar-like white patch: an irregularly outlined and sharply demarcated white area in the center of the lesion. In nonpolarized light dermoscopy appears as a white scar-like area and in polarized lightThis glossary term has not yet been described. dermoscopy as bright white areas with or without bright white linear streakslines radial (always at periphery) streaks Reed nevus melanoma recurrent nevus (chrysalis-like structures)

Other dermoscopy criteria

8 5 DF FIGURE 2.jpg
  • Ring-like or donut-shaped globules (Figure 2): The pigment network located toward the center of the lesion often ceases to look like a reticulated mesh but rather begins to resemble “ring-like” globular structures
  • White network : white lines surrounding small islands of brown pigment or surrounding globuleThis glossary term has not yet been described.-like (i.e., “ring-like”) structures.
  • Homogenous areas with brown color.
  • Vascular structuresThis glossary term has not yet been described.: The most common vascular structuresThis glossary term has not yet been described. are erythema, dotted vesselstiny pinpoint vessels flat melanocytic lesions inflammatory diseases Bowen disease, comma vesselslinear curved short vessels dermal nevi, and hairpin vesselsThis glossary term has not yet been described.. Less frequently, glomerular vesselsThis glossary term has not yet been described., linear–irregular vessels, linear vesselsLinear mildly curved vessels considered irregular when different sizes shapes and curves with a haphazard or random distribution are presented and considered regular when short and fine (thin) linear vessels prevail various diagnoses in a radial arrangementThis glossary term has not yet been described., and polymorphous/atypical vessels are visible.
  • Rarely comedo-like openings[[Comedo like openings]], scale, ulceration, peripheral collarette fissures, ridges and mamillatted surface.

Dermoscopy pattern:

The following ten demoscopic patterns have been associated with dermatofibromas:

Delicate pigment network throughout (Figure 3)


Peripheral delicate pigment network and central white scar-like patch

Peripheral delicate pigment network and central white network

Peripheral delicate pigment network and central homogenous pigmentation

White network throughout (Figure 4)

8 5 DF FIGURE 4.jpg

Homogenous pigmentation throughout

White scar-like patch

White scar-like patch throughout

Multiple focal white scar-like patches

Peripheral homogenous pigmentation and central white scar-like patch

Peripheral homogenous pigmentation and central white network

Atypical Pattern

Dermatofibromas showing atypical pigment networkNetwork with increased variability in the color, thickness, and spacing of the lines of the network; asymmetrically distributed; gray color, atypical scar-like patch, atypical homogeneous pigmentation or their irregular distribution within the lesion (Figure 5).

8 5 DF FIGURE 5.jpg


Hemosiderotic or aneurysmal dermatofibromaDermatofibromas are hard solitary slow-growing papules (rounded bumps) that may appear in a variety of colours, usually brownish to tan; they are often elevated or pedunculated. A dermatofibroma is associated with the dimple sign; by applying lateral pressure, there is a central depression of the dermatofibroma.:

usually manifest a multicomponent or atypical dermoscopy pattern with central bluish/reddish homogenous areas in combination with white structures, peripheral delicate pigment network, and vascular structures. Sometimes, blue homogeneous pigmentation throughout is observed (Figure 6).

8 5 DF FIGURE 6.jpg

Lipidized dermatofibroma:

usually manifests with the presence of single/multiple foci of yellow coloration/pigment.

Atypical variants:

variants that mimic other entities such as “melanomaThis glossary term has not yet been described.-like dermatofibromas”, “basal cell-like dermatofibromas”, “vascular tumor-like dermatofibromas”, “collision tumor-like dermatofibromas” and “psoriasisThis glossary term has not yet been described.-like dermatofibromas”

ReferencesThis is material contained in a footnote or bibliography holding further information.:

  1. Zaballos et al.: Dermoscopy of dermatofibromas: a prospective morphological study of 412 cases. Arch Dermatol 2008;144:75-83. PMID: 18209171. DOI.
  2. Ferrari et al.: Typical and atypical dermoscopic presentations of dermatofibroma. J Eur Acad Dermatol Venereol 2013;27:1375-80. PMID: 23176079. DOI.