Accuracy of Cyst Versus Solid Diagnosis in the Breast Using Quantitative Transmission (QT) Ultrasound

RATIONAL AND OBJECTIVES: This study aims to evaluate the diagnostic utility of breast imaging using transmission ultrasound. We present readers’ accuracy in determining whether a breast lesion is a cyst versus a solid using transmission ultrasound as an adjunct to mammography. MATERIALS AND METHODS: This retrospective multi-reader, multi-case receiver operating characteristic study included 37 lesions seen on mammography and transmission ultrasound. Cyst cases were confirmed as cysts using their appearance on handheld ultrasound. Solid cases were confirmed as solids with pathology results. Fourteen readers performed blinded, randomized reads with mammog-raphy + quantitative transmission scan images, assigning both a confidence score (0–100) and a binary classification of cyst or solid. A 95% percentile bootstrap confidence interval (CI) was computed for the readers’ mean receiver operating characteristic area, sensitivity, and specificity. RESULTS: Using the readers’ binary classification of cyst or solid lesions, the mean sensitivity and specificity were 0.933 [95% CI: 0.837, 0.995] and 0.858 [95% CI: 0.701, 0.985], respectively. When the readers’ confidence scores were used to distinguish a cyst versus solid, the mean receiver operating characteristic area was 0.920 [95% CI: 0.827, 0.985]. CONCLUSIONS: Transmission ultrasound can provide an accurate assessment of a cyst versus a solid lesion in the breast. Prospective clinical trials will further delineate the role of transmission ultrasound as an adjunct to mammography to increase specificity in breast evaluation.