Dermoscopy and In Vivo Confocal Microscopy Findings of Basal Cell Carcinomas in Xeroderma Pigmentosum Patients

Xeroderma pigmentosum (XP) is a rare inherited disorder with a high incidence of malignant tumours. Literature data on dermoscopic and in vivo reflectance confocal microscopy (RCM) findings in patients with XP are very limited. Dermoscopic findings in 32 biopsy-proven BCCs and RCM findings in 10 biopsy-proven BCCs developed in seven XP patients were reviewed. Of 32 BCCs, 28 were pigmented. On dermoscopy, BCCs exhibited multiple grey-blue globules/dots (81, 3), short-fine telangiectasias/fine arborising vessels (65, 6), multiple grey-blue ovoid nests (53, 1), white structures (white-red structureless areas/shiny white areas/lines/strands) (56, 3), arborising vessels (37, 5), brown nests/globules/dots (28, 1), spoke-wheel structures (9, 4), leaf-like areas (9, 4), ulceration (28, 1), peripheral network (21, 9), and multiple aggregated yellow-white globules (3, 1). In 10 lesions in which further imaging with RCM was performed, RCM findings differentiated BCC from other tumours, including primary melanoma. Although the dominancy of pigmented structures may imitate melanoma clinically, dermoscopy is a valuable tool in the early diagnosis of BCCs in patients with XP. For suspicious lesions, RCM can help in differentiating pigmented BCC from primary melanoma.