Initial clinical experience with a new MRI vacuum-assisted breast biopsy device

To report initial clinical experience with a new previously unreported vacuum-assisted device (EnCor MR, SenoRx, Aliso Viejo, CA) for magnetic resonance imaging (MRI)-guided breast biopsy and to compare this device with previously reported technologies.

A prospective study of MRI-guided vacuum-assisted breast biopsies using the EnCor device was undertaken. Lesions targeted for biopsy were occult on mammography, ultrasound, and physical examination. Histologic results were obtained for all cases. Patients with benign, concordant results underwent clinical and imaging follow-up. Cases with discordant, high-risk, or malignant results were referred for surgical biopsy.

A total of 55 biopsies were performed in 47 patients. All biopsies were technically successful. Histologic results yielded malignancy in 10 (10/55, 18%) of the 55 lesions and high-risk or atypical lesions in 7 (7/55, 13%) of the cases. All of these patients have had surgical follow-up, with four (4/55, 7%) underestimations. There were three (3/55, 5%) discordant cases. 35 (35/55, 64%) lesions yielded benign concordant results. Of these, six (6/35, 17%) lesions were removed surgically, with confirmation of the MR-guided biopsy results. Twenty (20/35, 57%) lesions have undergone at least 6-month follow-up MRI, with resolution or stability of the MRI findings.

The EnCor breast biopsy device has comparable results to those previously reported for other MRI-guided vacuum-assisted technologies.