MRI-guided breast biopsy: influence of choice of vacuum biopsy system on the mode of biopsy of MRI-only suspicious breast lesions.

Abstract

The purpose of this study was to evaluate two systems of MRI-guided vacuum-assisted biopsy and to investigate the influence of the choice of system on the choice of biopsy mode in the care of patients with lesions found only at MRI. Over a period of 3 years, a total 349 patients underwent MRI-guided tissue sampling of 475 lesions found only at MRI. The lesions were sampled by needle localization plus excisional biopsy or by vacuum-assisted biopsy. Two different systems were used for MRI-guided vacuum-assisted biopsy. During the first half of the study period, a handheld system was used, and during the second half, a console system was used. The procedural advantages and disadvantages, size of lesions biopsied, and time needed for vacuum-assisted biopsy were recorded. The distribution of the type of intervention (needle localization or vacuum-assisted biopsy) used to manage MRI-only lesions during the two study periods also was assessed. The average diameter of lesions sampled with vacuum-assisted biopsy was 19.2 mm with the handheld system and 10.4 mm with the console system (p < 0.039). The average biopsy time was 69 minutes for the handheld system and 39 minutes for the console system (p < 0.005). Of the total of 170 MRI-only lesions biopsied with the handheld system, 121 (71%) were sampled by localization and 49 (29%) by vacuum-assisted biopsy. Of the total 305 MRI-only lesions biopsied with the console system, 38 (12%) were sampled by localization and 267 (88%) by vacuum-assisted biopsy. Because of the procedural advantages of use of the console-based system, smaller lesions were biopsied in less time and with higher operator confidence. This result translated into a major shift in the care of patients with MRI-only lesions away from lesion localization toward increased use of MRI-guided vacuum-assisted biopsy.