Impact of nerve sparing in robot‐assisted radical prostatectomy on the risk of positive surgical margin and biochemical recurrence

Abstract

Objectives: Nerve sparing may increase positive surgical margin rate during radical prostatectomy. Our objective was to analyze the positive surgical margin rate and location as well as its impact on biochemical recurrence according to nerve sparing procedure in robot-assisted radical prostatectomy. Methods: We included 814 patients treated with robot-assisted radical prostatectomy between 2009 and 2021, and evaluated the impact of nerve sparing on positive surgical margin and biochemical recurrence using logistic regression and Cox models. Results: Unilateral nerve sparing and bilateral nerve sparing were performed in 152 (18.6%) cases and 118 (14.5%) cases, respectively. On multivariable analysis, in addition to nerve sparing, bilateral nerve sparing, but not unilateral nerve sparing was associated with an increased risk of positive surgical margin compared with non-nerve sparing. Positive surgical margin at any location increased the risk of biochemical recurrence. During unilateral nerve sparing, positive surgical margin in nerve sparing side, but not in non-nerve sparing side was associated with increased risk of biochemical recurrence on multivariate analysis. Conclusions: Taken together, surgeons need to notice an increased risk of biochemical recurrence associated with positive surgical margin when performing nerve sparing in robot-assisted radical prostatectomy, and then need to choose the patients suitable for nerve sparing.

Editorial Comment to Impact of nerve sparing in robot‐assisted radical prostatectomy on the risk of positive surgical margin and biochemical recurrence

“…In this study, the indications for NS were T stage ≤T2 with evaluations, including digital rectal examination and magnetic resonance imaging (MRI), and International Society of Urological Pathology grade group ≤3. A comparison of clinical and pathological stages showed that the number of cases with T stage ≥T3 increased with pathological stage from 9.2% to 32.2% in all cases, from 3.9% to 26.3% in unilateral NS, and from 0% to 14.4% in bilateral NS 4 . Staging in preoperative evaluation cannot predict the pathological stage accurately.…”

“…3 Komori et al reviewed 814 cases of robot-assisted radical prostatectomy with respect to NS and cancer control. 4 A multivariate analysis adjusted for several factors that affected cancer control concluded that bilateral NS techniques increased PSM more than non-NS ones, and unilateral NS techniques increased PSM on the NS side with an increased BCR risk. 4 The indication for NS may contribute to the increased PSM and BCR.…”

“…4 A multivariate analysis adjusted for several factors that affected cancer control concluded that bilateral NS techniques increased PSM more than non-NS ones, and unilateral NS techniques increased PSM on the NS side with an increased BCR risk. 4 The indication for NS may contribute to the increased PSM and BCR. In this study, the indications for NS were T stage ≤T2 with evaluations, including digital rectal examination and magnetic resonance imaging (MRI), and International Society of Urological Pathology grade group ≤3.…”

“…A comparison of clinical and pathological stages showed that the number of cases with T stage ≥T3 increased with pathological stage from 9.2% to 32.2% in all cases, from 3.9% to 26.3% in unilateral NS, and from 0% to 14.4% in bilateral NS. 4 Staging in preoperative evaluation cannot predict the pathological stage accurately. In the study, the number and sites of positive biopsies, cancer occupancy on biopsy, and prostate imaging reporting and data system evaluation on MRI were not considered when determining the indication for NS, which could have increased PSM on the side of NS.…”

“…2,4 Although NS is beneficial 1 and should be performed when possible, its possible adverse effects on cancer control should be considered. 3,4 Prostate cancer location should be determined using all possible modalities, including prostate needle biopsy and MRI findings, to determine the appropriate indication for NS and reduce PSM and BCR rates. 2…”