Purpose: The purpose of this study was to compare three different biopsy devices on false-negative and underestimation rates in MR-guided, vacuum-assisted breast biopsy (VABB) of MRI-only lesions.
Methods: This retrospective, single-center study was IRB-approved. Informed consent was waived. 467 consecutive patients underwent 487 MR-guided VABB using three different 8-10-gauge-VABB devices (Atec-9-gauge,A; Mammotome-8-gauge,M; Vacora-10-gauge,V). VABB data (lesion-type, size, biopsy device, histopathology) were compared to final diagnosis (surgery, n = 210 and follow-up, n = 277). Chi-square, and Kruskal-Wallis tests were applied. P values < 0.05 were considered significant.
Results: Final diagnosis was malignant in 104 (21.4 %), high risk in 64 (13.1 %) and benign in 319 (65.5 %) cases. Eleven of 328 (3.4 %) benign-rated lesions were false-negative (1/95, 1.1 %, A; 2/73, 2.7 %, M; 8/160 5.0 % V; P = 0.095). Eleven high-risk (11/77, 14.3 %) lesions proved to be malignant (3/26, 11.5 % A; 4/12, 33.3 % M; 4/39, 10.3 % V; P = 0.228). Five of 34 (14.7 %) DCIS were upgraded to invasive cancer (2/15, 13.3 %, A; 1/6, 16.6 % M; 2/13, 15.3 %, V; P = 0.977). Lesion size (P = 0.05) and type (mass vs. non-mass, P = 0.107) did not differ significantly.
Conclusion: MR-guided VABB is an accurate method for diagnosis of MRI-only lesions. No significant differences on false-negative and underestimation rates were observed between three different biopsy devices.
Key points: • MR-guided VABB is an accurate procedure for the diagnosis of MRI-only lesions. • Similar false-negative and underestimation rates allow all three different MR-guided VABB devices for clinical application. • High-risk lesions should undergo surgery due to a substantial underestimation rate. • Agreement between MR-guided VABB and final diagnosis (benign/malignant) was 95.5% (465/487).
Keywords: Breast cancer; MR imaging; MR-guided biopsy; MRI-only lesions; Vacuum assisted breast biopsy.