Assistant Professor University of British Columbia
Introduction: Routine pathologic assessment of neurovascular bundles during robot assisted laparoscopic prostatectomy (RALP) enables nerve sparing surgery without negatively affecting oncologic outcomes; however, many urologists do not have access to rapid frozen sections interpreted by genitourinary pathologists. We hypothesized that stimulated Raman histology (SRH) may allow surgeons to identify positive margins intra-operatively. Methods: 23 subjects underwent RALP with surgical margin resections conducted per surgeon assessment from pre-surgical and surgical factors. Pre-operatively all subjects underwent a 3 Tesla multiparametric prostate MRI (reporting per PI-RADSv2) indicating region of dominant tumor with degree of suspicion and location for possible ECE. Surgeons resected and imaged ~5mm samples from prostate bed along bilateral neurovascular bundles and/or areas of concern with a clinical stimulated Raman histology (SRH) microscope (raman spectra 2845cm-1 and 2930cm-1). Samples ground truth was provided by pathologic processing with hematoxylin and eosin staining or frozen section after SRH visualization. Results: 11 subjects had extra-prostatic extension (EPE), 8 of which had multifocal EPE. 7 subjects had a positive surgical margin, 6 of which had a non-focal positive margin. 10 of the 11 subjects with pathologic EPE had an associated MRI region of interest with broad capsular contact. 121 individual SRH margin assessments (mean 5.5) were conducted, with a mean time per assessment of 7.5minutes. The accuracy of surgical team SRH interpretation of resected margins was 95.5%, with a sensitivity of 83.3% and a specificity of 98.3%. All positive SRH margins were extra-prostatic and associated with EPE in a sextant zone in or adjacent to the MRI region of interest. Conclusions: SRH can provide surgeons with a rapid tool for accurate identification of PCa at surgical margins in real-time during RALP. SOURCE OF Funding: None
