M.C. Cho

Comparison of positive surgical margin rates in prostate cancer: Open versus robot assisted laparoscopic radical prostatectomy

INTRODUCTION AND OBJECTIVES: We evaluated the impact of nerve sparing during robot assisted radical prostatectomy (RARP) on postoperative continence outcomes in a single surgeon, single center propensity score matched study. METHODS: The study population consisted of 2362 patients who underwent RARP for localized prostate cancer by a single surgeon (VP) from January 2008 through May 2014. A query of our Institutional Review Board approved registry identified 92 men with non-nerve sparing (NNS, group 1) RARP who were computermatched in a 1:1 ratio to 92 patients with complete nerve sparing (CNS: bilateral full nerve sparing, group 2) RARP and 92 patients with partial nerve sparing (PNS: unilateral full nerve sparing with or without contralateral partial nerve sparing and bilateral partial nerve sparing, group 3) RARP using a propensity score matched algorithm. Perioperative and postoperative functional outcomes for three groups were compared. Degree of nerve sparing (NS) was graded intra-operatively by the surgeon independently at either side as complete, partial or none. Postoperative continence was defined as using no pads per day. RESULTS: When NNS group was compared with PNS group, all pre-operative clinical characteristics, intraoperative and pathological parameters were comparable. At 3 months, the continence rate was significantly higher and mean time to continence was significantly lower in PNS group in comparison to NNS group (91.3% vs 72.1% respectively1⁄40.01 and 2.19 months vs 3.91 months1⁄40.03 ). Similarly, on comparing CNS group with NNS group at 3 months, the continence rate was significantly higher and mean time to continence was significantly lower in CNS group in comparison to NNS group (92.2% vs 72.1% respectively1⁄40.01 and 2.03 months vs 3.91 months respectively1⁄40.02 ). However, the continence rate was comparable in 3 groups at 1 year (94.1%,92.7% and 84.7% respectively in CNS, PNS and NNS groups; p 1⁄40.43) CONCLUSIONS: Neurovascular bundles (NVB) preservation (irrespective of complete or partial) during robot assisted radical prostatectomy results in an earlier return of postoperative urinary continence. A significantly higher number of patients achieve urinary continence between 0-3 months after surgery, in comparison to propensity matched patients with non-nerve sparing procedure. Beyond 3 months post-surgery, there was no difference in ability to achieve urinary continence regardless of NVB preservation status.