Alice Carboni, Presenter: Nothing to Disclose

Alfonso Fausto MD, Abstract Co-Author: Research Consultant, General Electric Company

Cosimo Damiano Forte, Abstract Co-Author: Nothing to Disclose

Luca Volterrani, Abstract Co-Author: Nothing to Disclose

To evaluate ultrasound elastography using strain ratio (SR), a relative quantification approach for breast lesions characterization.

One hundred forty-seven consecutive patients (52±14 years) with a total of 156 breast lesions underwent to ultrasound elastography. For each lesion evaluation, a movie of at least 5 seconds was recorded. Technical accuracy was assessed automatically. To obtain dynamic SR evaluation a rounded small region of interest was depicted inside the fat tissue (F), in the glandular tissue (G) and the in the lesion (L), preferably at the same depth. Mean value of the ratio between G and F resulted in background tissue composition elasticity: R1; mean value of L/F resulted in lesion elasticity: R2, both evaluated in arbitrary unit (au). A two-years follow-up and pathology results were the standard of reference. Discordances between BI-RADS classification and R2 values were also evaluated. Mann-Whitney test, ROC analysis and Chi-square with Yates correction were used.

A high technical accuracy was obtained in all examinations. Twenty-seven out of 156 lesions were cysts, 25 with a typical three-layer artifact. Seventeen were malignant lesions (13 IDC, 2 IDC+DCIS, 1 DCIS and 1 ILC) and 112 benign lesions (90 fibroadenomas, 7 lymph nodes, 5 fat necrosis, 5 sclerosing adenosis, 2 adenosis, 2 mastitis, 1 radial scar). R1 values were 1.6±0.7au and 1.2±0.9au (mean±SD); R2 values were 6.1±2.5au and 1.9±1.3au for malignant and benign lesions, respectively (P<0.0001). A threshold of 3.3au showed a sensitivity and specificity of 88% and 87%, respectively with an AUC of 93%. Fifteen false positive were 12 fibroadenomas, five with calcifications, 2 sclerosing adenosis and 1fat necrosis. Two false negative were 1 IDC+DCIS and 1 DCIS. In 31 out of 156 lesions discordance between BI-RADS classification and R2 values were found (1 IDC, 1 DCIS, 1 IDC+DCIS and 14 fibroadenomas, 6 complex cysts, 3 sclerosing adenosis, 2 mastitis, 2 adenosis and 1 radial scar, P<0.0001).

Relative quantification of ultrasound elastography allows to find high levels of diagnostic accuracy in characterizing breast tumors above all in downgrading BI-RADS 3 and 4 lesions.

A high specificity is found using a relative quantification ultrasound elastography despite of background tissue composition. The application of this technique could reduce useless biopsy.

Carboni, A, Fausto, A, Forte, C, Volterrani, L, Clinical Value of Relative Quantification Ultrasound Elastography in Characterizing Breast Tumors.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14003420.html