High-frequency ultrasound: an essential non-invasive tool for the pre-therapeutic assessment of basal cell carcinoma

Aim: While histology remains the “gold standard” for cutaneous tumoral pathology, high-frequency ultrasound (HFUS) was shown to play a significant role in the non-invasive, pre-therapeutic assessment of skin tumors. The aim of our study was to determine whether there is a significant correlation between the ultrasound (US) and histological measurements of basal cell carcinoma (BCC) tumor depth. Materials and Methods: The present study retrospectively analyzed clinical, dermoscopy, HFUS and histological examinations of 90 patients (52 men and 38 women) with histologically confirmed BCC, with focus on tumor depth index (DI). Results: On clinical examination, 54 lesions were nodular (32 presented ulcerations) and 36 superficial lesions. Dermoscopy showed suggestive signs of BCC, most frequently “in focus” arborising superficial vessels (n=81), blue-grey ovoid nests (n=48) and specks of brown pigment (n=7). HFUS revealed well-defined (n=88) or poorly defined (n=2) hypoechoic, vascularized lesions, with inhomogeneous structure (n=90) and characteristic hyperechoic dots (n=36). A strong correlation (Pearson’s r=0.92) between the HFUS (mean measured US depth = 1.33 mm) and histological (mean measured histological depth = 1.47 mm) DI of the investigated skin lesions was found, although significant differences (p<0.001 – t-test for paired samples) between the two measurements were observed. Conclusions: HFUS provides reliable information about BCC depth of invasion that cannot be otherwise obtained prior to surgery. In this manner, it completes the preclinical evaluation and can have an impact on the choice of the optimal therapeutic method.