M. Borghesi, F. Manferrari R. Schiavina, , A. Bertaccini, E.Brunocilla, S. Concetti, A. Baccos,C.V. Pultrone, V.
Vagnoni, D. Diazzi, F. Mengoni, G. Martorana
Background
The aim of this study is to evaluate the status of positive surgical margins (PSMs) in our radical prostatectomy specimens, comparing their incidence between the radical retropubic prostatectomy(RRP) and laparoscopic-assisted radical prostatectomy(LRP). We also studied the correlations between the surgical technique, the nerve-sparing approach (NSS) and the incidence of PSMs, stratifying our results by pathological stage.
Material and Methods
We evaluated a cohort of 1.879 patients who underwent radical prostatectomy for prostate cancer at our Institution between October 1995 and May 2011. Of these patients, 1448 (77%) were treated with RRP, and the remaining 431 of them (23%) underwent to LRP. In 473 patients
(25.3%) we performed a nerve-sparing surgery. We evaluated the incidence of positive surgical margins, and then we compared the stage-related incidence of PSMs, in both of these tecniques
(RRP vs LRP and NSSvs non-NSS).
Results
Pathological stage of prostate cancer at the histological examination was pT2 in 1042 patients
(55.5%); pT3a in 534 patients (28,4%); pT3b/pT4 in 303 patients (16,1%). Positive surgical margins
(PSMs) were globally diagnosed in 673 patients (35.8%). The overall incidence of PSMs was greater in patients with locally advanced disease than organ-confined ones (50.8% in pT3b/pT4 stage;
43.4% in pT3a stage; 27.5% in pT2 stage). Among pT2 patients, we observed the presence of PSMs in 215 (28.1%) patients who underwent to RRP and in 72 (25.9%) patients who underwent to LRP, with no statistically significant difference between two groups (p=0.263). We performed NSS in
230 (30%) pT2 RRP patients and in 106 (38%) LRP ones; in this patients, we observed a PSMs rate of 27.8% (64 patients)in the first (RRP) group and of 24.5% (26 patients) in the second (LRP) group, without statistically significant difference between two groups (p=0.504). Similar results were found in pT3a patients, with an incidence of PSMs in 182 (43.3%) RRP patients and 50 (43.9%) LRP patients (p=0.501); in pT3a patients, we performed NSS in 75 (17.8%) RRP patients and in 30
(26.3%) LRP ones; in this patients, we observed a PSMs rate of 46.6% (35 patients) in the first
(RRP) group and of 30% (9 patients) in the second (LRP) group, with a statistically significant difference between LRP and RRP (p=0.05).Among pT3b/pT4 patients, we observed an incidence of
PSMs in 133 (50.4%) RRP patients and 21 (50.8%) LRP patients (p=0.408).We performed NSS in 31
(11.7%) pT3b\pT4 RRP patients and in 5 (12.9%) LRP ones; in this patients, we observed a PSMs

rate of 48.4% (15 patients) in the first (RRP) group and of 80% (4 patients) in the second (LRP) group, without statistically significant difference between two groups (p=0.482)
Discussion:
In our large cohort of we observed a similar incidence of positive surgical margins (PSMs) among the same pT stage patients
Conclusions
Radical retropubic prostatectomy and laparoscopic-assisted radical prostatectomy are substantially equivalent in term of PSMs incidence, also in NSS patients, with no statistically significant difference between this two tecniques.