An increasing number of nonpalpable breast lesions are identified due to screening mammography and breast magnetic resonance imaging (MRI). After appropriate diagnostic imaging workup, many of these image-detected abnormalities require a biopsy for pathologic confirmation. The positive predictive value of mammography (the number of cancers diagnosed per number of biopsies recommended) historically has ranged from 15% to 35%.1 Fortunately, a substantial number of these lesions are initially evaluated with percutaneous image-guided breast biopsy, providing a less costly, less invasive method to obtain an accurate diagnosis without sacrificing accuracy. After a benign diagnosis is obtained with a minimally invasive image-guided biopsy, no further workup is recommended, and the patient is placed in an established follow-up protocol. The goal of reserving open surgical biopsy for definitive clinical management and eliminating it for the sole purpose of diagnosis is increasingly being accomplished.
Even with the advent of image-guided needle biopsy, there is still a need for localization and excision of nonpalpable (and some palpable) lesions. Despite the potential advantage of image-guided percutaneous breast biopsy, some patients are only satisfied with complete surgical removal of their mammographic abnormality. Other patients may not have access to facilities with equipment for stereotactic procedures because of their insurance plans or locale. There are also certain patient characteristics, such as obesity or arthritic conditions and certain lesion types and locations (diffuse calcifications/posterior near the chest wall) that make image-guided biopsy with stereotactic guidance difficult or inappropriate. Excision is also indicated after an image-guided percutaneous breast biopsy if the diagnosis is malignant or high risk (such as atypical lobular or ductal hyperplasia) or if there is discordance between the radiographic impression and the pathologic result.2,3 Medical judgment is crucial in any image-guided breast biopsy program. If the procedure was technically unsatisfactory, the imaging was less than ideal, or poor quality tissue cores were obtained, the physician should not hesitate to recommend a surgical excision. Moreover, because most of these abnormalities are nonpalpable, a localization procedure would be necessary, which traditionally was performed with mammography guidance but increasingly is accomplished with intraoperative ultrasound.
Open surgical biopsy with preoperative wire localization has several drawbacks. The failure of removing the targeted lesion has been reported as high as 22%.4,5 The ability to accomplish a successful biopsy of a nonpalpable breast abnormality may be limited by substandard preoperative wire placement in radiology; dislodgement, migration, or transaction of the wire either pre- or intraoperatively; the failure of the surgeon to excise the lesion accurately; or the failure to obtain a specimen radiograph to confirm that the lesion was adequately removed. Finally, it may be difficult for the pathologist to identify a very small lesion accurately within a large volume of excised tissue.4-6
Patients report high anxiety with the wire placement procedure with episodes of syncope in 9% to 20% of patients who are awake and usually upright.4-6 Many patients report that the localization ...