Diagnostic performance of ultrasound elastography in differentiating malignant from benign breast microcalcifications: a case-control study.

Objective: To evaluate the sensitivity and specificity of ultrasound elastography in differentiating between malignant and benign breast microcalcifications through a case-control study.

Methods: A total of 300 female patients were enrolled in this study, equally divided between malignant (n = 150) and benign (n = 150) microcalcification groups. The malignant cases were histologically confirmed as ductal carcinoma in situ or invasive breast cancer, while benign cases were confirmed through histology or follow-up as fibroadenoma, fibrocystic changes, or benign calcifications. Ultrasound elastography parameters, including elastic modulus (kPa), strain ratio, and elasticity scores, were measured and compared between groups. Multiple logistic regression analysis was performed to identify independent predictors, and diagnostic performance was evaluated using ROC curve analysis.

Results: Malignant lesions demonstrated significantly higher mean elasticity values compared to benign lesions (88.3 ± 16.2 kPa vs. 45.7 ± 9.8 kPa, P < 0.001). The strain ratio and elasticity scores were also significantly elevated in the malignant group (both P < 0.001). Multivariate analysis identified elastic modulus (OR = 1.09, 95%CI: 1.06-1.12, P < 0.001) and strain ratio (OR = 2.50, 95%CI: 1.70-3.80, P < 0.001) as independent predictors of malignancy. Using an optimal cutoff value of 62 kPa for elasticity, the diagnostic sensitivity was 88.0% (95%CI: 81.5-92.8%) and specificity was 86.7% (95%CI: 79.5-91.9%), with an accuracy of 89.0%. The area under the ROC curve (AUC) for elasticity alone was 0.95 (95%CI: 0.92-0.98), which improved to 0.97 (95%CI: 0.94-0.99) when combined with strain ratio (P = 0.018). High interobserver agreement was demonstrated (Kappa = 0.84, 95%CI: 0.79-0.88), and Bland-Altman analysis confirmed excellent measurement reliability.

Conclusion: Ultrasound elastography demonstrates high diagnostic accuracy in differentiating between malignant and benign breast microcalcifications, with excellent reproducibility and reliability. The combination of elasticity values and strain ratio provides superior diagnostic performance compared to single parameters alone, suggesting its potential as a valuable tool in clinical practice for the evaluation of breast microcalcifications.