Amy Fair Brother, Utah Valley University
Physical Sciences
Results from a 2010 pilot study indicated that multiple parameters in high-frequency (HF) ultrasound spectra (20-80 MHz) correlate to a range of tissue pathologies in surgical margins from breast conservation surgery (BCS). One of these parameters, peak density, was particularly effective at discriminating between normal, atypical, and malignant patholUtah Conference on Undergraduate Research 2015 100 ogies. Subsequently, Utah Valley University and the Huntsman Cancer Institute initiated a follow-up study to further investigate this approach. Objectives: The purpose of this study was to determine the sensitivity and specificity of HF ultrasound for differentiating malignant tissue from normal tissue in BCS surgical margins. Methods: A 73-patient blind study was conducted with conventional pathology used as the gold standard for assessing the HF ultrasound method. Specimens were delivered by the surgeon’s team immediately following resection and ultrasonically tested outside the surgical suite. The margins were approximately 3x20x20 mm, and were oriented using a small staple inserted by the surgeon in one corner and a stitch on one side. The margin was tested at 2-5 locations on the specimens using our methodology and then sent to pathology for their analysis. 498 specimens were tested from 73 patients. That corresponded to 1112 positions collected from the margins. The data was then analyzed for malignancy using peak density, and then correlated with the traditional pathology. Results: Results from the current study indicate that peak density can differentiate between malignant and nonmalignant pathologies with an accuracy of 73.8%. The correlation between pathology and peak density has a high level of statistical significance compared to random chance, with p = 0.000078 (Fisher’s Exact test). The results also provide data for improving the technique. For example, approximately 3 times more false positives were observed than false negatives, indicating the peak density threshold used for identifying malignant pathology is most likely too low and should be adjusted to a higher value. Conclusions: Results from this study showed that HF ultrasound has the potential to provide rapid, intraoperative evaluation of surgical margins, thereby decreasing the number of additional surgeries for patients and thus increasing the quality and efficacy of surgical treatment for breast cancer.