Objective: 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.
Materials and methods: 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.
Results: 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.
Conclusion: 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.