Strain Elastography in differentiating benign versus malignant breast masses: Demystifying its role
Aanchal Bhayana, Geetika Khanna, Neha BagriObjectives:
The purpose of our study was to evaluate and compare the diagnostic accuracies of strain elastography versus conventional ultrasound in differentiating benign and malignant breast masses, using histopathology as the gold standard. Our study also adds to the literature by describing strain elastography features of a few unusual entities, namely, multiple juvenile fibroadenomas, tubercular mastitis, and secretory carcinoma in an adolescent girl.
Materials and Methods:
Both conventional ultrasound and strain elastography were performed in solid breast masses in 100 female patients; the largest mass was evaluated in patients with multiple lesions. Breast Imaging Reporting and Data System (BIRADS) criteria were used for conventional ultrasound diagnosis. Strain elastography parameters used for the diagnosis of malignancy were color coding (Tsukuba score ≥ 4), size ratio >1, and strain ratio >3.85. The conventional ultrasound and strain elastography diagnoses were both compared with histopathology. Diagnostic accuracy and receiver operator characteristic (ROC) curve analysis with area under the curve (AUC) were calculated for both techniques.
Results:
Conventional ultrasound had a specificity of 81.5%, Positive predictive value (PPV) of 82.14%, and AUC (ROC) 0.938. Strain elastography using a strain ratio cut-off of 3.85 (by ROC curve analysis) showed specificity of 88.89%, PPV of 88.46%, and AUC (ROC) 0.977. Using histopathology as the gold standard, strain elastography revealed a statistically significant improvement in specificity with p < 0.05.
Conclusion:
The complementary use of strain elastography improves diagnostic accuracy of conventional ultrasound and should, therefore, be recommended for inclusion in the routine breast ultrasound protocol, thereby reducing the number of unnecessary benign breast biopsies.