Ultrasonographic features of superficial and nodular basal cell carcinoma

To describe the ultrasonographic findings of surface and nodular basal cell skin cancer (BCC) using high frequency ultrasonography.

We examined 60 primary BCCs in different locations with the High Frequency Ultrasound (HFU) system DUB Skin Scanner using 75 MHz and 30 MHz probes. Epidermis, dermis, and depth of tumors spread in the region of interest (ROI) were measured. Visually unchanged, contralateral skin areas were examined as the control. Results: The surface BCC most often had elongated contours, clear margins and hypoechoic structure, while the nodular BCC had round or oval outlines and diffusely hypo-heterogeneous structure with clear margins. Sclerodermiform BCCs were visualized as hypoechoic areas of irregular shape penetrating in the dermis, with wavy fuzzy margins. The average thickness of the surface BCC in the US examination was 556.28±136.95 μ, the nodular BCC thickness was 2439.71±865.92 μ and the sclerodermiform thickness was 1500±325.33 μ. A statistically significant increase in the average thickness of tumors of the nodularand scleroderma forms was observed in comparison with the surface clinical variant (p<0.05). Hyperechoic inclusions were observed in 11% of the surface BCC's and in the 100% of the nodular BCC's. Their average number was 2±0.57 and 4±4.8, with the average area of 0.03±0.02 mm2 and 0.04±0.03 mm2 (p>0.05), respectively. In the surface BCC, they were mainly located along the periphery of the hypoechoic zones. In nodular BCC, the inclusions had a peripheral and combined (center and peripheral) distribution.

Ultrasound allows differentiating BCC as diffuse-heterogeneous, hypoechoic, formations in the dermis with distinct contours. Depending on the clinical picture, they differ in form, depth of bedding, as well as in the quantitative ratio and distribution of the point hyperechoic structures in them.