Diagnostic Utility of Third-Look, Contrast-Enhanced Sonography Followed by Needle Biopsy for MRI, But Not Second-look Ultrasonography-detected Breast Lesions.

Abstract

To clarify the diagnostic utility of third-look, contrast-enhanced ultrasonography (CEUS) for MRI-detected breast lesions undetectable by unenhanced, second-look ultrasonography (MRI+/US- lesions). Clinical stage 0-IIA breast cancer patients who underwent CEUS for incidental MRI+/US- lesions (n=27; cohort 1) and patients with breast lesions detected only by MRI, to be examined by CEUS (n=15; cohort 2), were retrospectively analyzed. Of the 42 MRI+/US- lesions, 23 (55%) were detected by CEUS and then examined by needle biopsy. Pathological examination showed that 10 of these 23 lesions were malignant. None of the 19 lesions undetected by CEUS were found to be histologically malignant or developed malignancy with a median follow-up of 18.5 months. The accuracy, sensitivity, and specificity of CEUS plus needle biopsy were 98%, 91%, and 100%, respectively. Third-look CEUS followed by needle biopsy is useful in the initial diagnosis of MRI+/US- lesions.