Assessment of Cutaneous Melanoma by Use of Very- High-Frequency Ultrasound and Real-Time Elastography

OBJECTIVE. The primary objective of this study was to evaluate the usefulness of very-high-frequency ultrasound as tool for assessment of skin melanoma by investigation of the correlation between the ultrasound measurement of the thickness of a melanoma and the histopathologically measured Breslow index. The secondary objective was to assess the potential role of real-time elastography in the preoperative evaluation of skin melanoma. SUBJECTS AND METHODS. The study included 42 cutaneous melanoma lesions in 39 adult subjects examined in the division of ultrasound of a department of radiology between September 2011 and January 2015. Gray-scale sonographic features at 40 MHz (thickness, echogenicity, contour) and real-time strain elastographic (qualitative and semiquantitative, strain ratio) characteristics were evaluated and compared with the pathologic results. RESULTS. The melanoma lesions had a homogeneous hypoechoic appearance with a regular contour and stiff or medium consistency. The mean difference between Breslow index and ultrasound thickness was -0.05 mm (95% CI, -0.24 to 0.13 mm), sustaining the absence of significant differences between these two measurements. A strong relation was identified between real-time elastographic appearance and strain ratio for the relations between lesion and hypodermis and between lesion and neighboring dermis (p < 0.002) or hypodermis. CONCLUSION. Our study showed that very-high-frequency ultrasound and real-time elastography can be useful examinations for comprehensive preoperative evaluation of cutaneous melanoma.