Background Magnetic resonance (MR) permits the detection of some malignant lesions that cannot be identified with mammography or ultrasonography. The characterization of these MR-only detectable lesions often requires a biopsy. Purpose To evaluate the technique, the feasibility and the accuracy of freehand 3T MR-guided VAB for the characterization of suspicious, MR-only detectable lesions and to compare VAB results with surgical pathology and follow-up imaging results. Material and Methods During 2010-2015, 118 women who were referred for MR-guided VAB were retrospectively reviewed. All BI-RADS MR 4 and 5 lesions and some BI-RADS MR 3 lesions (according to clinical context and patient anxiety) were scheduled to undergo biopsy. Results A total of 123 suspicious lesions were retrospectively selected. Technical failures occurred in only two cases (1.6%) due to the location of the lesions. Histopathological results revealed 59 benign lesions (48%), 27 high-risk lesions (22%), and 35 malignant lesions (28.4%). Surgical pathology results led to the reclassification of eight B3 lesions: one proved to be a ductal carcinoma in situ, while seven presented with invasive features. B3 underestimation also occurred in 29% of the cases. MR follow-up was achieved for all the benign lesions and no false-negative cases were observed. No complications, 3T-related artefacts, or difficulties were observed. Conclusion Freehand 3T MR-guided VAB was found to be a valid, safe, fast, and inexpensive alternative to surgical histology.
Keywords: 3T magnetic resonance imaging (MRI); Breast cancer; MR-guided biopsy; MRI-only lesions; vacuum-assisted breast biopsy.