The Sentinel Margin: Intraoperative ex-vivo Specimen Mapping Using Relative Fluorescence Intensity. Clinical cancer research : an official journal of the American Association for Cancer Research van Keulen, S., Nishio, N., Birkeland, A., Fakurnejad, S., Martin, B. A., Forouzanfar, T., Cunanan, K., Colevas, A. D., van den Berg, N. S., Rosenthal, E. L. 2019

Abstract

PURPOSE: Despite major advancements in surgical oncology, the positive margin rate for primary head and neck cancer resection remains around 15-30%. In particular, the deep surface margin is the most challenging to adequately assess. Inadequate margins are directly correlated to poor survival, and as such, mitigation of these rates is critical to improve patient outcomes. We have developed an ex vivo imaging strategy that utilizes fluorescence intensity-peaks (relative to background signal) of an injected anti-epidermal growth factor receptor antibody conjugated to a fluorescent probe to locate potential close or positive margins on the deep surface of the resected tumor specimen.EXPERIMENTAL DESIGN: Twelve patients with head and neck cancer scheduled for surgery received systemic administration of a tumor-specific contrast-agent (panitumumab-IRDye800). After surgical resection, the tumor specimen was imaged using a fluorescence imager. The three highest fluorescence intensity-peaks on the deep surface of the specimen were isolated and correlated to histology to determine the margin distance at these regions.RESULTS: Relative fluorescence peak-intensities identified the closest margin on the deep surface of the specimen within 2.5 minutes. The highest intensity-peak consistently (100%) detected the closest margin to the tumor. The difference in tumor margin distance between the first and second highest fluorescence intensity-peak averaged 2.1±1.4mm. The tumor-margin difference between the second and third highest peak averaged 1.6±0.6mm.CONCLUSIONS: Fluorescence intensity-peaks can identify the region on the specimen where tumor is closest to specimen's edge on the deep surface. This technique could have broad applications in obtaining adequate margins in oncological surgery.

View details for DOI 10.1158/1078-0432.CCR-19-0319

View details for PubMedID 31142505