50732 The Use of High Frequency Ultrasound In Preoperative Melanoma Measurements

Accurate preoperative evaluation of melanoma is essential for appropriate surgical planning and successful excision. Technological advancements have introduced high-frequency ultrasound (HFUS) as a safe alternative to visualize cutaneous tumor characteristics including depth. This study evaluates the precision of HFUS in measuring melanoma dimensions against the gold standard of histopathology, and aims to understand its value in preoperative melanoma assessment. A systematic review of English-language publications within PubMed, CINAHL, Embase, Clarivate, and Cochrane electronic databases was conducted in March 2023 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. Out of 1197 initially identified articles, 37 studies met the inclusion criteria. Of the 2093 melanomas imaged, most occurred on the trunk and head/face, with superficial spreading melanoma being the most common. Maximum ultrasound frequencies across studies ranged from 13MHz to 100MHz and tumor numbers ranged from 5 to 264. Correlation coefficients between HFUS and histopathology ranged from 0.417 to 0.997 (median 0.94, mean 0.89, SD 0.13). Overall, lower frequency probes (<20MHz) were less accurate in assessing melanoma thickness when compared higher-frequency probes, with a cumulative mean correlation coefficient of 0.828 compared to 0.927 (20MHz-25MHz) and 0.967 (>70MHz). Studies demonstrate higher HFUS accuracy of preoperative staging and defining surgical margins in melanomas that are >0.75mm. HFUS may serve as a valuable supplementary tool for preoperative melanoma assessment, with increased accuracy in thicker tumors. Sonographic frequencies lower than 20MHz are less reliable in assessing tumor depth, and frequencies greater than 70MHz tend to have stronger correlations with histopathology.