Dermoscopic semiology: further insights into vascular features by screening a large spectrum of nontumoral skin lesions

Summary Background  Dermoscopic vascular criteria remain poorly evaluated and analysed. The increasing number of descriptions of amelanotic melanoma showing isolated vascular dermoscopic findings adds interest to this topic. Objective  To evaluate and classify the dermoscopic vascular structures seen in nontumoral dermatoses (NTD). Patients and methods  The affected skin of 414 consecutive patients suffering from a variety of 31 different biopsy‐proven NTD was evaluated with the dermoscope and photographed with the Dermaphot camera. Results  The dermoscopic vascular structures seen in NTD consisted of round dotted and globular vessels, linear vessels and glomerular vessels. In addition, structureless coloured patches were also found. In some NTD the distribution of the vascular structures took on special arrangements. The most common vascular findings were the linear and the rounded vessels, which were distributed either homogeneously throughout the lesion or were present together with other vascular or pigmented features in a mixed pattern. Conclusion  The present study proposes a new classification of dermoscopic vascular features based on the screening of a large spectrum of nontumoral dermatoses. This list may be useful to define further dermoscopic semiology and to understand the vascular features most relevant to the diagnosis not only of different NTD but also of pigmented and amelanotic melanoma.