Background

Patients with suspicious lesions on MRI that cannot be detected with another modality may undergo MRI guided biopsy. The MRI biopsy may induce anxiety and may be uncomfortable with the breast in compression which may be exacerbated by the length of the procedure. Software has been developed by certain companies to streamline and increase ease of the MRI-guided biopsy. We performed a study to see if this software decreases the length of the procedure. We also will see if software leads to differences recommendation, concordance, and subsequent cancer if the biopsy was benign.

Materials and Teaching Points

We conducted a retrospective review of patients from dates from December 2016 to December 2018 and included the first 100 consecutive patients to have undergone an MRI guided biopsy using software localizing approach and the first 99 consecutive patients to have undergone an MRI guided biopsy using a manual localizing approach. The software utilized by the institution was the Hologic software which requires a dedicated breast coil to successfully localized the target (Figure 1). MRI-guided biopsy with Manual Localization Technique When positioning the patient for breast biopsies one must ensure the require target is within the interventional grid to adequately cover the lesion of interest (Figure 2). The radiologist then evaluates compression and places a fiducial manually within the interventional grid to use as a reference for manual technique (figure 4). Manual Localization Technique: The protocol uses LAVA VIBRANT Flex for all sagittal views: slice thickness of 3mm; matrix size 256 x 192, field of view (FOV) 34-36, bandwidth of 200KHz, flip angle 10, The parameters for the second scan are axial scan with a slice thickness of 2mm and a FOV of 24-26. MRI-guided biopsy with Computer-aided software technique Follows the same principals as the manual technique. But one key measurement here is to ensure that the entirely of the fiducial is cover during the first diagnostic scan. If fiducial is not included computer registration will fail (Figure 5). Software Localization Technique: The protocol uses LAVA VIBRANT Flex for all sagittal views: slice thickness of 3mm; matrix size 256 x 192, field of view (FOV) 34-36, bandwidth of 200KHz, flip angle 10, The parameters for the second scan are axial scan with a slice thickness of 2mm and a FOV of 24-26

Results

We compared the results between 100 patients who underwent an MRI-guided biopsy with software localizing approach and 99 patients who underwent an MRI-guided biopsy with manual localizing approach. There was no difference in size of target lesion, concordance of pathology results, follow up plan, malignant diagnosis, interval malignancy, and months of follow up between both groups. There were statistically more samples taken in the software group than the manual group (9.1 vs 8.3, p = 0.004). The procedure was statistically longer in manual group than the software group (33.0 minutes vs. 25.6 minutes, p = 0.0001) and the number of scans was more in the manual group than the software group (9.6 vs. 6.9, p = 0.0001).

	Software	Manual	p
Number of samples	9.1 +/- 2.1	8.3 +/1 1.47	0.0041
Procedure length, minutes	25.6 +/- 7.9	33.0 +/- 16.1	0.0001
Number of scans	6.9 +/- 2.4	9.6 +/- 2.4	0.0001
Mass/Focus (as opposed to Nonmass Enhancement)	56.60%	55%	0.887
Size, cm	1.6 +/- 1.6	1.8 +/- 1.9	0.541
Concordant pathology results	98.00%	99%	0.621
Definitive plan given (as opposed to 6-month f/u)	83.8	85	0.847
Malignancy Diagnosis	17%	19%	0.716
Follow up, months	27.8 +/- 14.9	29.7 +/- 17.0	0.416
Interval malignancy at time of follow up	0%	2%	0.497

Conclusion

Software localizing approach in MRI-guided biopsy results in a shorter procedure and fewer scans which may help with the anxiety and discomfort of the patient. There is no difference in other outcome between when using software localizing approach versus manual localizing approach.

Acknowledgements

No acknowledgement found.