Successful intraoperative margin assessment in DCIS and invasive breast cancer with diffusion-weighted MRI using the ClearSight™ system

Aim:

Aim of our study is to evaluate the performance of the ClearSight™ system (ClearCut Medical, Ltd.) in assessing surgical margins for DCIS and IBC in breast conserving surgery (BCS).

Material and Methods:

The ClearSight™ system utilizes a diffusion-weighted-imaging (DWI) protocol to create 2D surface maps showing T2*, a MR parameter related to the tissue's apparent diffusion coefficient (ADC), with a depth penetration of 1 – 1.5 mm. ADC is a highly accurate differentiator for malignant versus benign tissue.

From November 2017 a prospective, blinded Post Marketing study (N = 110), evaluating the performance of the ClearSight™ system is being conducted in the Breast Centre at the Agaplesion Markus Krankenhaus, Frankfurt, Germany. After standard evaluation with ultrasound and/or X-ray, the specimens are being scanned with the ClearSight™ system and compared with the final histopathology results on a margin per margin bases.

Results:

Breast specimens' margins from 25 patients were analysed. Pursuant to the BCS, 146 margins were scanned by the ClearSight™ system. In comparison with the pathology findings this results in a sensitivity of 75% (95% CI: 56 – 94%), and specificity 86% (95% CI: 80%-92%). The re-operation rate was 36% (9/25), however, the ClearSight™ found 8/9 (89%) margins be positive. If the scan results would had been unblinded to the surgeon only 1/25 would have required re-excision surgery, resulting in a theoretical re-operation rate of 4%.

Conclusion:

Despite the limited sample size of this preliminary analysis, the initial results suggest that the technology promises to reduce re-excision rates well below the currently observed standard.