Basal cell carcinoma invasion depth determined with 30 and 75 MHz high-frequency ultrasound and histopathology - a comparative study.

AIM: To compare the depth spread of basal cell carcinoma (BCC) measured by histological examination and high-frequency ultrasound (HFUS) imaging with 30-MHz and 75-MHz probes. MATERIALS AND METHODS: HFUS skin imaging was used to examine 27 BCCs. A specialized high-resolution digital ultrasound imaging system DUB (TPM GmbH, Germany) with 75-MHz and 30-MHz probes was used. After HFUS scanning, the BCCs biopsy samples were collected by punch biopsy or surgical excision for the morphological examination. Based on the histomorphology results obtained, the tumors were divided into thin (≤1 mm invasion depth) and thick (>1 mm invasion depth). Each BCC spread depth was measured during the HFUS examination with 75-MHz and 30-MHz ultrasound probes and morphological examination. RESULTS: Thin BCCs average invasiondepth measured histologically was 0.494±0.212 mm. Its average depth obtained with HFU examination with 75-MHz and 30-MHz probes was 0.591±0.265 and 0.734±0.123 mm, respectively. High, statistically significant correlation betweenthe histological and 75 MHz HFU measurements was obtained (r=0.870). The correlation was weak (r=0.290) when using a 30 MHz transducer. The average thick BCC invasion depth values obtained with the histological examination and 30 MHz HFUS scanning was 1.845±0.718 mm and 1.995±0.699 mm, respectively. High, statistically significant (r=0.951) correlation between the thick BCC spread depth measured with 30 MHz transducer and histomorphological examination was obtained. CONCLUSIONS: In cases of BCCs with thickness of ≤1 mm, there was a high correlation (r=0.870) of the tumor spread depth between micromorphological measurements and the results obtained using a 75 MHz transducer and in cases of BCCs with thickness of >1 mm, a very high correlation (r=0.951) of the tumor spread depth was observed between histomorphometry and30 MHz transducer measurements.

Ultrasonographic features of superficial and nodular basal cell carcinoma.

AIM: To describe the ultrasonographic findings of surface and nodular basal cell skin cancer (BCC) using high frequency ultrasonography. MATERIALS AND METHODS: 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. CONCLUSIONS: 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.