BACKGROUND

Basal cell carcinoma (BCC) is the most common malignant skin tumor. High-frequency ultrasound scanning is widely used for the noninvasive diagnosis of BCC. However, ultrasonographic features of different clinical types of the tumor have not been sufficiently studied.

OBJECTIVE

To study the ultrasonographic features of superficial, nodular, and scleroderma-like forms of BCC using 30 and 75 MHz high-frequency transducers.

MATERIAL AND METHODS

The study included 88 patients. A high-resolution ultrasound system was used to examine 116 abnormal sites. A 75 MHz transducer was used for foci located at a depth of 1 mm or less, and a 30 MHz transducer for foci at a depth of more than 2 mm. We measured the thickness of the epidermis and derma, depth of tumor spreading in the areas of interest, and echogenicity of abnormal foci and adjacent derma.

RESULTS

All clinical variants of BCC were detected as hypoechogenic foci on the scans. The superficial BCC foci had an oblong shape, well-visualized borders, and homogeneous structure, while nodular BCC foci had round or oval shapes, sharp edges, and diffuse heterogeneous structure. Sonograms of scleroderma-like basal cell carcinoma showed hypoechogenic masses of 3 varieties: the first was characterized by rounded or irregularly shaped foci with kidney-shaped processes and blurred boundaries, the second by band-shaped foci with blurred boundaries, and the third by a conglomerate of several elongated foci with clear contours connected by hyperechogenic interlayers. There was a significant increase in the depth of spread of nodular form foci compared to superficial and scleroderma-like types (p<0.001), which also differed from each other in favor of the latter (p<0.05). The density of hypoechogenic areas and surrounding derma was highest in scleroderma-like basal cell carcinomas of the skin.