The additional role of contrast-enhanced ultrasound in identifying lesions in pathological nipple discharge patients: a prospective study comparing with DCE-MRI.

Objective: To evaluate the auxiliary role of contrast-enhanced ultrasound (CEUS) in the etiological diagnosis of pathological nipple discharge (PND) and compare its effectiveness with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

Methods: In this prospective study conducted from March 2021 to February 2024, PND patients underwent breast ultrasound and DCE-MRI after initial history and physical examination. Lesions were categorized as mass or non-mass-like on baseline US and assessed for vascularity using color Doppler. CEUS was utilized to refine the breast imaging reporting and data system (BI-RADS) classification. Logistic regression identified risk factors, and diagnostic performance was evaluated using receiver operating characteristic curve analysis.

Results: A total of 116 lesions from 112 PND patients were analyzed. CEUS-assisted ultrasound showed increased specificity (ranging from 50.0% to 80.0% compared to US alone, p = 0.009) while maintaining sensitivity. Of the 81 patients who underwent DCE-MRI, CEUS demonstrated a higher positive predictive value (83.3% vs. 75.5%), with comparable negative predictive values (97.0% vs. 96.4%). CEUS was particularly effective in accurately diagnosing benign lesions that were overestimated by DCE-MRI and in identifying ductal carcinoma in situ with greater precision than US alone.

Conclusion: The auxiliary use of CEUS with ultrasound improves the specificity and positive predictive value in diagnosing PND-associated malignancies and serves as a valuable secondary imaging method to DCE-MRI, potentially reducing unnecessary biopsies of benign lesions.

Advances in knowledge: CEUS can enhance the diagnostic accuracy of PND, effectively differentiating benign from malignant lesions, and its integration into clinical practice could offer significant benefits in patient management.