Dermoscopic Features of Lichen Amyloidosis in Caucasians—A Case Series and Literature Review

Abstract

Primary cutaneous amyloidosis (PCA) is characterized by the extracellular deposition of amyloid in the skin without systemic involvement. It comprises several clinical variants, the most common of which are macular amyloidosis (MA) and lichen amyloidosis (LA). PCA is frequently observed in Asians, while it is considered to be very rare in Caucasians. In the latter population, the condition often poses a diagnostic challenge. Dermoscopy has already been proved to be a useful, non-invasive diagnostic tool in various non-neoplastic skin diseases. In the paper, we present three Caucasian patients (skin phototypes I–II) with histologically confirmed LA. Under dermoscopy, central white hubs with grayish-brown dots and globules were observed in all three cases. Vascular structures were present in two cases and had the morphology of red globules and thick, unfocused branching lines intersecting the white hubs. A comprehensive review of the literature retrieved twelve papers presenting the dermoscopic features of PCA, including five articles on the dermoscopy of LA. The vast majority of these studies have been conducted on the Asian population, and there is a lack of data on the dermoscopic findings for patients with skin type I or II. The literature review revealed that MA and LA share several dermoscopic similarities (the presence of a white central hub and grayish dots), but also display distinct features. Compared to the dermoscopic features of LA in darker skin phototypes, our patients presented less pronounced pigmentation and more evident vascular structures. Nevertheless, further studies are needed in order to reliably evaluate the dermoscopic features of PCA in various ethnicities.