Comparative Study of Pattern-Based Versus Size Ratio Ultrasound Strain Elastographic Techniques on Breast Masses

Shear wave versus strain elastography of breast lesions-The value of incorporating boundary tissue assessment

PURPOSE

This prospective study compares the diagnostic performance of strain elastography (SE) based on the elastogram to B-mode (E/B) size ratio to shear-wave elastography (SWE) incorporating assessment of boundary tissue stiffness.

METHODS

In this prospective study, 81 women consented to undergo ultrasound (US) elastographic assessment prior to biopsy of their mass(es). A total of 101 masses were evaluated with SE and SWE using a single machine (Siemens Acuson S2000). The histopathologic diagnosis was used as the reference standard. The sensitivity, specificity and area under curve (AUC) were obtained for SE and SWE.

RESULTS

The sensitivity and specificity of SE using the E/B ratio was 94.7% (95% CI: 87.6 100) and 81.0% (95% CI: 71.3 90.1) respectively. For SWE the sensitivity and specificity was 73.7% (95% CI: 59.7 87.7) and 82.5% (95% CI: 73.2 91.9) respectively. The AUC for SE was higher (0.878) compared to SWE (0.697).

CONCLUSION

SE elastography using the E/B ratio yields diagnostic performance which is superior to SWE incorporating assessment of peripheral stiffness.

Diagnostic and Predictive Values of Strain Ratios in the Regions of Interests in Reference Tissue for Breast Tumor

Purpose

To investigate the diagnostic and predictive value of strain ratios in the regions of interests (ROIs) in reference tissue for breast tumor.

Patients and Methods

A total of 707 lesions in 665 consecutive patients were examined with B-mode Breast Imaging-Reporting and Data System (BI-RADS) and Ultrasonic elastography (UE). Elasticity score (ES) and strain ratio (SR) in each lesion were calculated. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value of BI-RADS, ES, SR1, SR2, BI-RADS combined with ES (BI-RADS+ES), BI-RADS combined with SR1 (BI-RADS+SR1), and BI-RADS combined with SR2 (BI-RADS+SR2). The sensitivity, specificity, and areas under the ROC curves (Az) were obtained. Scatter plots were generated to demonstrate the correlation between SR1 and SR2. Kruskal-Walls H-test, Mann–Whitney U-test and one-way ANOVA were performed to evaluate SRs and tumor-related variables. Multiple linear regression analysis was carried out to determine variables independently associated with SRs.

Results

BI-RADS had high sensitivity and low specificity in the diagnosis of breast tumor. The specificity of BI-BADS combined with ES or SR was even higher. The Az value of BI-RADS+ES or BI-RADS+SRs was higher than that of BI-RADS (P < 0.001). The Az value of ES was higher than those of SR1 and SR2 (P < 0.001), and those of SR1 and SR2 were similar. SR1 and SR2 were highly positively correlated. There was no statistical difference between Az values of BI-RADS+ES, BI-RADS+SR1, and BI-RADS+SR2. Indistinct margin, high histologic grade, histological type, and negative human epidermal growth factor receptor (Her-2) were associated with SR1 and SR2. Progesterone receptor (PR) status and molecular subtype were associated with SR2. Histologic grade and tumor margin were significantly associated with SR1, and tumor margin was associated with SR2.

Conclusion

SRs in different ROIs in the reference tissue at the same depth showed no different diagnostic value for breast tumor. Both SR1 and SR2 could be useful in assessing the biological characteristics of invasive breast carcinoma.