The impact of nerve sparing on incidence and location of positive surgical margins in radical prostatectomy

Objective: • To examine whether nerve-sparing surgery (NSS) is a risk factor for positive surgical margins (PSMs) in patients with either organ-confined prostate cancer or extracapsular extension (ECE).

Patients and methods: • Clinicopathological outcome data on 945 consecutive patients treated with radical prostatectomy (RP) were prospectively collected. • All patients underwent RP (bilateral, unilateral or non-NSS) by one surgeon between 2002 and 2007. • Risk of PSMs and their locations with respect to NSS was determined by multivariate logistic regression analysis adjusting for preoperative risk factors for PSMs within pT2, pT3a and pT3b tumours.

Results: • Overall a PSM was identified in 19.6% of patients in an unscreened population with mean prostate-specific antigen (PSA) level of 8.1 ng/mL. • There was no significant difference in rates of PSMs between NSS groups on multivariate analysis (P= 0.147). • There was no significant difference in pT2 (P= 0.880), pT3a (P= 0.175) or pT3b (P= 0.354) tumours. • The only significant predictor of PSMs was preoperative PSA level (risk ratio 1.289, P= 0.006). • There was no significant difference in the location of PSMs except for the pT3a group, where the patients that had bilateral NSS were at higher risk of a posterolateral PSM (P= 0.028).

Conclusions: • With appropriate selection of patients, NSS does not increase the risk of PSMs, whether the cancer is organ confined or ECE is present. • The adverse impact of the NSS procedure in the hands of an experienced surgeon is minimal and is a realistic compromise to obtain the increase in health-related quality of life offered by NSS.