Incidence and location of positive surgical margins following open, pure laparoscopic, and robotic-assisted radical prostatectomy and its relation with neurovascular preservation: a single-institution experience.

Abstract

To evaluate whether robotic-assisted radical prostatectomy (dvRP) provides adequate local control of the disease, incidence of positive surgical margins (PSMs) obtained with dvRP was compared with that of laparoscopic radical prostatectomy (LRP) and with that of open radical retropubic prostatectomy (RRP) performed in a single institution by the same surgeons. We also studied whether neurovascular bundle preservation modified PSM rates. The records were retrospectively reviewed from electronic medical data, and three groups of 100 patients were organized. Group1 included 100 patients who underwent RRP prior to the incorporation of minimally invasive techniques. Group2 included the first 100 patients who underwent LRP, and group3 was made up of the first 100 patients who underwent dvRP. All surgical specimens were analyzed by the same pathologist. We used the technique described by Patel etal. for dvRP. LRP was performed using a five-trocar extraperitoneal approach as previously published by the authors. RRP was performed using retrograde dissection as described by Walsh etal. The final decision of preserving neurovascular bundles was made during surgery. Using D'Amico's risk classification, the dvRP group had a lower percentage of patients with low risk (dvRP versus LRP p=0.017; dvRP versus RRP p=0.0108). No statistically significant differences were found within high- and intermediate-risk groups. A higher percentage of patients with pT3 disease was found in the dvRP group compared with the RRP group (p=0.0408). There were no statistically significant differences regarding PSMs among groups (RRP: 25, LRP: 14, dvRP: 18), although when we compared the total number of PSMs we found that the dvRP group had 18 PSMs versus 21 and 50 PSMs for LRP and RRP, respectively. All three groups had more PSMs located posterolaterally. There was a higher percentage of nerve-sparing procedures in the dvRP group (dvRP: 91 patients, LRP: 47 patients, RRP: 5 patients) (p<0.0001). No statistically significant differences were found in the PSM rates between the three techniques analyzed. The number of nerve-sparing procedures in the dvRP group was statistically higher. However, this preservation did not modify PSM rates.