Usefulness of Shear Wave Elastography in Determining the Tumor Extent of Basal Cell Carcinomas.

OBJECTIVES: The purpose of this study was to investigate the value of shear wave elastography (SWE) in determining tumor extent of basal cell carcinomas (BCC), and thereby determine the optimal surgical margins (OSM). METHODS: 10 patients (40 surgical margins) with BCC were collected, the visual observation boundaries (VOB) were marked, and the SWE parameters of soft tissues were measured 1 mm intervals in "3, 6, 9, 12" clock directions, starting from VOB. Then tumors were resected with a 5 mm surgical margin outward expansion of VOB. All specimens were examined pathologically 1 mm intervals from VOB in four clock directions. With the positive margins furthest from the tumor as the real tumor boundaries (RTB) and the negative margins closest to the tumor as the optimal surgical margins (OSM). The SWE parameters were compared between these two groups. RESULTS: The elasticity ratio (Eratio ) of average young's modulus between region of interest and adjacent normal soft tissue had statistically significant differences between groups (P = .000), while other parameters show no difference. The Eratio of RTB and OSM were 1.22 ± 0.14 and 0.99 ± 0.07. The area under the ROC curve was .947. Taking 1.075 as the threshold of Eratio for the diagnosis of tumor extent, the sensitivity, specificity and accuracy were 87.5%, 90.0% and 90.0%. The surgical margins designed according to OSM were better than those designed according to VOB + 5 mm (P = .000). CONCLUSIONS: The Eratio of SWE is helpful in determining tumor extent of BCC. This is beneficial for surgical margin designing.

High-Frequency Ultrasound and Shear Wave Elastography in Quantitative Differential Diagnosis of High-Risk and Low-Risk Basal Cell Carcinomas.

OBJECTIVES: The purpose of this study was to investigate the value of high-frequency ultrasound and shear wave elastography (SWE) in quantitative differential diagnosis of high-risk and low-risk basal cell carcinomas (BCCs). METHODS: A total of 52 BCCs confirmed by surgical pathology were studied. Taking pathologic subtypes as reference, all the cases were classified as high-risk BCCs or low-risk BCCs. High-frequency ultrasound parameters and SWE parameters recorded preoperatively were retrospectively analyzed. The differences of two groups were compared. RESULTS: There were 12 high-risk BCCs and 40 low-risk BCCs. The maximum infiltration depth (MID) and average Young's modulus (Eave ) of high-risk BCCs were 5.76 ± 2.56 mm and 31.61 ± 12.36 kPa, whereas of low-risk BCCs were 4.29 ± 1.77 mm and 20.04 ± 4.74 kPa, respectively, P < .05. The area under the receiver operator characteristic curve of MID and Eave were 0.714 and 0.811, P > .05. Taking 5.5 mm of MID and 24.45 kPa of Eave as the threshold for the diagnosis of high-risk BCCs, the sensitivity, specificity, and accuracy were 58.3%, 82.5%, 76.9% and 75.0%, 82.5%, 80.8%, P > .05. CONCLUSIONS: The MID and Eave of the lesion can be used to determine the recurrence risk of BCCs and provide a reference for the development of individualized treatment plans.