Interventional breast MR imaging: clinical use of a stereotactic localization and biopsy device.

PURPOSE: To evaluate the usefulness of preoperative magnetic resonance (MR) imaging-guided stereotactic localization and core biopsy of suspicious breast lesions that are visible at breast MR imaging alone (ie, that are clinically, mammographically, and ultrasonographically occult), with the goal of integrating this technique into the diagnostic and therapeutic work-up of MR-suspicious lesions in a clinical setting.
MATERIALS AND METHODS: A stereotactic breast biopsy device was used for needle placement in and guide wire localization of 97 lesions in 66 patients or core biopsy of five lesions in five patients; all lesions were visible at MR imaging. Interventions were performed with MR guidance on a 0.5- or 1.5-T system.
RESULTS: Lesion localization and resection were successful in 95 of the 97 lesions; two of the lesions were not resected in spite of correct guide wire localization. In this series, 53 (55%) of 97 lesions proved malignant (11 [21%] in situ; 42 [79%] invasive). Lesions were 4-19 mm (mean, 8.7 mm); all invasive cancers corresponded to a pT1 tumor stage. Location of the lesion in the parenchyma (retroareolar or prepectoral) did not interfere with accessibility.
CONCLUSION: MR imaging-guided stereotactic hook-wire placement and excisional biopsy are accurate and effective in managing lesions identified at only breast MR imaging. MR imaging-guided core biopsy holds promise for allowing a definite work-up of these lesions.