Pd61-07 neurovascular Structure-Adjacent Frozen-Section Examination (Neurosafe) Robotic Assisted Laparoscopic Radical Prostatectomy: Outcomes From 500 Consecutive Cases in the Uk

Abstract

INTRODUCTION AND OBJECTIVE: To report the United Kingdom's largest single centre experience of robotically assisted laparoscopic radical prostatectomies (RALP), using the neurovascular structure -adjacent frozen-section (NeuroSAFE) technique. We describe its' efficacy on histopathological and functional outcomes, to aid units in their early stages of adoption of this technique.METHODS: We prospectively collected data from November 2012 e December 2019 on 520 patients who underwent RALP with NeuroSAFE at our Institution. Exclusion criteria was pre-operative indication to perform an extra-fascial nerve spare or wide local excision prostatectomy, including salvage RALP. Our Institution's database was analysed for false positive frozen section (FS) margins as confirmed on paraffin histopathological analysis; console and FS report time; functional outcomes of potency, continence, surgical margins and biochemical recurrence (BCR).RESULTS: The median (range) of operative console time of our NeuroSAFE RALPs was 145 (90e300) minutes. The mean time of FS processing to report was 35 minutes. In our cohort, positive FS was seen in 30.7% (160/520) of patients, with a confirmatory paraffin analysis in 91.8% of cases (147/160). The neurovascular bundles (NVBs) that underwent secondary resection, contained tumour in 26.8% (43/ 160) of cases. 77.5% T2, 22.3% T3 cancer was found on final prostate specimen analysis. Biochemical recurrence (BCR) was 6.7% (35/520), of which FS was positive in 40% (14/35) of those cases. Bilateral nerve spare (NS) RALP was statistically significant for potency, over wide excision due to positive FS. There was insufficient evidence of a statistically significant association of urinary incontinence and positive surgical margin rates according to NS or NVB resection.CONCLUSIONS: Our mid to long term results of NeuroSAFE RALP describes acceptable functional outcomes. NeuroSAFE enables intra operative confirmation of the oncologic safety of a NS procedure. Patients with a positive FS on NeuroSAFE can be converted to a negative surgical margin (NSM) by wide resection of the NVB. This spared 1 in 4 men from positive margins posterolaterally in our series. No other technique has been externally validated to offer intraoperative 'real time' feedback on the oncologic safety of NS RALP. Limitations are the absence of a matched contemporary cohort of NS RALP without NeuroSAFE in our centre; three surgeons with variable NVB preservation techniques and three Uro-pathologists.