Advantages Of Intraoperative Medical Hyperspectral Imaging (Mhsi) For The Evaluation Of The Breast Cancer Resection Bed For Residual Tumor.

709 Background: Medical Hyperspectral Imaging (MHSI) is a novel, camera-based method of imaging spectroscopy that integrates spatial & spectroscopic data from tissue in a simple image. Despite advances in surgery, adequate breast tumor resection is an issue with over 30% recurring locally. MHSI may provide noninvasive, rapid, & inexpensive evaluation of residual cancer in the tumor bed at the time of resection. Here, we demonstrate proof-of-principle in a preclinical rat model. Methods: Female Sprague-Dawley rats received 50mg/kg DMBA by gastric gavage at age 8wks to induce breast tumors. 21 rats developed multiple tumors. We studied 98 tumors and performed partial resection of 41 tumors, yielding 41 full tumor/partial resection/tumor bed sets for analysis. Tumor was exposed & resected, intentionally leaving a small (0.5mm) piece of residual tumor in the bed. Gross examination, MHSI & histopathology were recorded. MHSI using visible light system (HyperMed, Inc., Watertown, MA) provided 40μm resolution (field of view 4X6cm). Algorithms based on spectral characteristics of tissue type were developed to distinguish tumor & normal tissues. Primary endpoint was designation of tumor/normal tissue found to remain in the tumor bed by gross exam, MHSI algorithm, & histology. Results: Interim analysis on 16 full sets of tumor bed data (gross/MHSI/hist.) showed that MHSI correctly identified tumor in all cases & detected tumor in the resection bed of 0.5mm whereas standard histopathology failed to do so in 2 cases (agreement kappa = 0.75). Conclusions: MHSI may provide reliable data in near-real time with a convenient device for the surgeon in the operating room. MHSI shows promise for increasing sensitivity of detection of residual tumor over current surgical tissue sampling techniques. Follow-on studies in patients are planned. Supported by: CDMRP Concept Award, DAMD17-03-1-0767 BC024521, NIH-NIEHS I-P01 ES11624–03 Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration HyperMed HyperMed HyperMed HyperMed