To describe the dermoscopic features, including vascular structures and patterns associated with dermatofibromas in a large series of cases.
Digital dermoscopic images of the prospectively collected dermatofibromas were evaluated for the presence of multiple structures and patterns.
Dermatofibromas were collected in the Departments of Dermatology of the Hospital de Sant Pau i Santa Tecla, Tarragona, Spain, and Hospital de Sant Llatzer, Palma de Mallorca, Spain.
A total of 412 dermatofibromas (from 292 patients) with complete documentation were collected.
Main Outcome Measures
Frequency and intraobserver and interobserver agreement of the dermoscopic structures and patterns in dermatofibromas.
A total of 19 morphological dermoscopic structures were evaluated. Pigment network was observed in 71.8% (3% atypical pigment network), white scarlike patch in 57.0%, and a white network in 17.7%. Different vascular structures were observed in 49.5% (dotted vessels in 30.6%). Ten dermoscopic patterns were observed. The most common pattern seen in our series (34.7% of cases) was central white patch and peripheral pigment network, but in 65.3% of the cases, dermatofibromas presented different patterns including simulators of melanoma.
The most common pattern associated with dermatofibroma is the classic dermoscopic pattern (pigment network and central white patch), but this tumor has a wide range of presentations.