by Juanjuan Gu, Eric C. Polley, Redouane Ternifi, Rohit
Nayak, Judy C. Boughey, Robert T. Fazzio, Mostafa Fatemi, Azra Alizad
The Breast: VOLUME
54, P248-255, DECEMBER 01, 2020
Highlights
•Larger mass size and lower mass depth increase false
positives in breast SWE.
•Smaller mass size and increased mass depth increase false
negatives in breast SWE.
•Individualized elasticity cutoffs based on lesion size and
depth improves the specificity.
•Multifactorial analysis including age, individualized
cutoffs, BIRADS improves sensitivity/specificity.
•Mammographic breast density does not affect the SWE measurements
of breast masses.
Abstract
Purpose
To investigate the diagnostic role of new metrics, defined
as individualized-thresholding of Shear Wave Elastography (SWE) parameters, in
association with clinical factors (such as age, mammographic density, lesion
size and depth) and the BI-RADS features in differentiating benign from
malignant breast lesions.
Methods
Of 644 consecutive patients (median age, 55 years),
prospectively referred for evaluation, 659 ultrasound detected breast lesions
underwent SWE measurements. Multivariable logistic regression analysis was used
to estimate the probability of malignancy. The area under the curve (AUC),
optimal cutoff value, and the corresponding sensitivity, specificity, positive
predictive value (PPV) and negative predictive value (NPV) were determined.
Results
265 of 659 (40.2%) masses were malignant. Using two Emean cutoffs,
69.6 kPa for large superficial lesions (size >10 mm, depth
≤5 mm) and 39.2 kPa for the rest, the overall specificity,
sensitivity, PPV and NPV were 92.6%, 86.8%, 88.8% and 91.3%, respectively.
Combining multiple factors, including Emean with two cutoffs, age and
BI-RADS, the new ROC curve based on the malignancy probability calculation
showed the highest AUC (0.954, 95% CI: 0.938–0.969). Using the optimal
probability threshold of 0.514, the corresponding specificity, sensitivity, PPV
and NPV were 92.9%, 89.1%, 89.4% and 92.7%, respectively.
Conclusions
The false-positive rate can be significantly reduced when
applying two Emean cutoffs based on lesion size and depth. Moreover,
the combination of age, Emean with two cutoffs and BI-RADS can
further reduce the false negatives and false positives. Overall, this
multifactorial analysis improves the specificity of ultrasound while
maintaining a high sensitivity.
