(SST) Leica Proficinet Surgical Tumor Award (2023 Award Winner): Intraoperative in vivo Confocal Laser Endomicroscopy Imaging at Glioma Margins: Can We Detect Tumor Infiltration?
Research Fellow Barrow Neurological Institute Phoenix, Arizona, United States
Disclosure(s):
Yuan Xu, MD: No financial relationships to disclose
Introduction: Confocal laser endomicroscopy (CLE) is a new FDA-cleared intraoperative real-time cellular-resolution fluorescence-based imaging technology. Although proven to image brain tumor histoarchitecture rapidly in vivo during neuro-oncological surgeries, a main goal for successful intraoperative implementation is in vivo use at the margin region of primary invading brain tumors. However, until now its use specifically at the infiltrating glioma margins is not well studied.
Methods: Matching in vivo CLE images and tissue biopsies acquired at glioma margin regions of interest (ROIs) from two institutions were collected for analysis. All images were reviewed by four neuropathologists experienced in CLE. Based on cellularity, a 0-to-5 scoring system was implemented to score CLE and H&E images from each ROI. Based on the H&E scores, all ROIs were divided into a low-tumor-probability group (LTP, scores 0~2) and a high-tumor-probability group (HTP, scores 3~5). The concordance between the CLE scores and the H&E scores regarding tumor probability was determined. The interclass correlation coefficient (ICC) and diagnostic performance of the system were calculated. The interclass correlation coefficient of the scoring system was evaluated.
Results: 58 glioma margin ROIs were included for analysis. Interrater reliability of the scoring system (ICC=0.69, 95%CI: 0.40-0.83) is moderately high, although significantly lower than that of H&E (ICC=0.91, 95%CI: 0.86-0.94). ICCs for the LTP group (0.68, 95%CI: 0.40-0.83) and HTP group (0.68, 95%CI: 0.39-0.83) do not differ significantly. Concordance rate of CLE and H&E scores is 59%. Sensitivity and specificity of the scoring system are 79% and 35%. Positive and negative predictive values are 59% and 59%.
Conclusion : CLE can detect presence or absence of tumor infiltration at glioma margins. The proposed scoring system has good interrater reliability and diagnostic performance. These results suggest that along with the intraoperative telesurgery-pathology platform, CLE can potentially provide actionable histological information for optimizing brain tumor resection at glioma margins.
