***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: INTRODUCTION Lack of r and omized controlled trials ( RCTs ) that compare pure laparoscopic radical prostatectomy ( LRP ) with robot-assisted laparoscopic radical prostatectomy ( RALRP ) is an important gap of the literature related to the surgical treatment of the clinical ly localized prostate cancer ( PCa ) . AIM To provide the first prospect i ve r and omized comparison on the functional and oncological outcomes of LRP and RALRP for the treatment of the clinical ly localized PCa . METHODS Between 2007 and 2008 , 128 consecutive male patients were r and omized in two groups and treated by a single experienced surgeon with traditional LRP ( Group I-64 patients ) or RALRP ( Group II-64 patients ) in all cases with intent of bilateral intrafascial nerve sparing . MAIN OUTCOME MEASURES Primary end point was to compare the 12 months erectile function ( EF ) outcomes . Complication rates , continence outcomes , and oncological results were also compared . The sample size of our study was able , with an adequate power ( 1-beta > 0.90 ) , to recognize as significant large differences ( above 0.30 ) between incidence proportions of considered outcomes . RESULTS No statistically significant differences were observed for operating time , estimated blood loss , transfusion rate , complications , rates of positive surgical margins , rates of biochemical recurrence , continence , and time to continence . However , the 12-month evaluation of capability for intercourse ( with or without phosphodiesterase type 5 inhibitors ) showed a clear and significant advantage of RALRP ( 32 % vs. 77 % , P < 0.0001 ) . Time to capability for intercourse was significantly shorter for RALRP . Rates of return to baseline International Index of Erectile Function ( IIEF-6 ) EF domain score question naires ( questions 1 - 5 and 15 ) ( 25 % vs. 58 % ) and to IIEF-6 > 17 ( 38 % vs. 63 % ) were also significantly higher for RALRP ( P = 0.0002 and P = 0.008 , respectively ) . CONCLUSIONS Our study offers the first high-level evidence that RALRP provides significantly better EF recovery than LRP without hindering the oncologic radicality of the procedure . Larger RCTs are needed to confirm if a new gold-st and ard treatment in the field of RP has risen BACKGROUND Previous studies have shown that complications and biochemical recurrence rates after  radical prostatectomy ( RP )  vary between different surgeons to a greater extent than might be expected by chance . Data on urinary and erectile outcomes , however , are lacking . OBJECTIVE In this study , we examined whether between-surgeon variation , known as heterogeneity , exists for urinary and erectile outcomes after RP . DESIGN , SETTING , AND PARTICIPANTS Our study consisted of 1910 RP patients who were treated by 1 of 11 surgeons between January 1999 and July 2007 . INTERVENTION All patients underwent RP at Memorial Sloan-Kettering Cancer Center . MEASUREMENTS Patients were evaluated for functional outcome 1 yr after surgery . Multivariable r and om effects models were used to evaluate the heterogeneity in erectile or urinary outcome between surgeons , after adjustment for case mix ( age , prostate-specific antigen , pathologic stage and grade , comorbidities ) and year of surgery . RESULTS AND LIMITATIONS We found significant heterogeneity in functional outcomes after RP ( p<0.001 for both urinary and erectile function ) . Four surgeons had adjusted rates of full continence < 75 % , whereas three had rates > 85 % . For erectile function , two surgeons in our series had adjusted rates < 20 % ; another two had rates > 45 % . We found some evidence suggesting that surgeons ' erectile and urinary outcomes were correlated . Contrary to the hypothesis that surgeons " trade off " functional outcomes and cancer control , better rates of functional preservation were associated with lower biochemical recurrence rates . CONCLUSIONS A patient 's likelihood of recovering erectile and urinary function may differ depending on which of two surgeons performs his RP . Functional preservation does not appear to come at the expense of cancer control ; rather , both are related to surgical quality OBJECTIVES To evaluate the pathologic and functional outcomes of patients with bilateral interfascial ( IF ) or extrafascial nerve-sparing ( EF-NSP ) techniques .  It is believed that the IF-NSP technique used during robotic-assisted radical prostatectomy ( RARP ) spares more nerve fibers , while EF dissection may lower the risk for positive surgical margins ( PSM ) . METHODS A prospect i ve data base was analyzed for RARP patients with bilateral IF- or EF-NSP technique .  Collected parameters included age , body mass index , prostate-specific antigen , clinical and pathologic Gleason score and stage , estimated blood loss , operative time , and PSM characteristics . Functional outcomes were evaluated with the use of the University of California Los Angeles Prostate Cancer Index question naire . Men receiving postoperative hormonal or radiation therapy were excluded from sexual function analysis . RESULTS A total of 110 and 703 cases with bilateral EF- and IF-NSP , respectively , were analyzed .  EF-NSP patients had higher prostate-specific antigen , clinical , pathologic stage , and pathologic Gleason score . PSM rate did not achieve statistically significant difference between groups . There was a trend toward lower pT3-PSM in the EF group ( 51 % vs 28 % ; P = .08 ) . Mid- and posterolateral PSM location were lower in the EF-NSP group , 11 % vs 37 % and 11 % vs 29 % , respectively ( P < .001 ) . The IF-NSP group patients achieved statistically significant better sexual function ( P = .02 ) and potency rates ( P = .03 ) at 12 months after RARP . CONCLUSIONS In lower risk patients , bilateral IF-NSP technique does not result in significantly higher PSM rates .  EF-NSP appears to reduce posterolateral and mid-prostate PSM . Men with bilateral IF-NSP demonstrate significantly better sexual function outcomes BACKGROUND Positive surgical margin ( PSM ) after  radical prostatectomy ( RP )  has been shown to be an independent predictive factor for cancer recurrence . Several investigations have correlated clinical and histopathologic findings with surgical margin status after open RP . However , few studies have addressed the predictive factors for PSM after robot-assisted laparoscopic RP ( RARP ) . OBJECTIVE We sought to identify predictive factors for PSMs and their locations after RARP . DESIGN , SETTING , AND PARTICIPANTS We prospect ively analyzed 876 consecutive patients who underwent RARP from January 2008 to May 2009 . INTERVENTION All patients underwent RARP performed by a single surgeon with previous experience of > 1500 cases . MEASUREMENTS Stepwise logistic regression was used to identify potential predictive factors for PSM . Three logistic regression models were built : ( 1 ) one using preoperative variables only , ( 2 ) another using all variables ( preoperative , intraoperative , and postoperative ) combined , and ( 3 ) one created to identify potential predictive factors for PSM location . Preoperative variables entered into the models included age , body mass index ( BMI ) , prostate-specific antigen , clinical stage , number of positive cores , percentage of positive cores , and American Urological Association symptom score . Intra- and postoperative variables analyzed were type of nerve sparing , presence of median lobe , percentage of tumor in the surgical specimen , gl and size , histopathologic findings , pathologic stage , and pathologic Gleason grade . RESULTS AND LIMITATIONS In the multivariable analysis including preoperative variables , clinical stage was the only independent predictive factor for PSM , with a higher PSM rate for T3 versus T1c ( odds ratio [ OR ] : 10.7 ; 95 % confidence interval [ CI ] , 2.6 - 43.8 ) and for T2 versus T1c ( OR : 2.9 ; 95 % CI , 1.9 - 4.6 ) . Considering pre- , intra- , and postoperative variables combined , percentage of tumor , pathologic stage , and pathologic Gleason score were associated with increased risk of PSM in the univariable analysis ( p<0.001 for all variables ) . However , in the multivariable analysis , pathologic stage ( pT2 vs pT1 ; OR : 2.9 ; 95 % CI , 1.9 - 4.6 ) and percentage of tumor in the surgical specimen ( OR : 8.7 ; 95 % CI , 2.2 - 34.5 ; p=0.0022 ) were the only independent predictive factors for PSM . Finally , BMI was shown to be an independent predictive factor ( OR : 1.1 ; 95 % CI , 1.0 - 1.3 ; p=0.0119 ) for apical PSMs , with increasing BMI predicting higher incidence of apex location . Because most of our patients were referred from other centers , the biopsy technique and the number of cores were not st and ardized in our series . CONCLUSIONS Clinical stage was the only preoperative variable independently associated with PSM after RARP . Pathologic stage and percentage of tumor in the surgical specimen were identified as independent predictive factors for PSMs when analyzing pre- , intra- , and postoperative variables combined . BMI was shown to be an independent predictive factor for apical PSMs BACKGROUND Apical dissection and control of the dorsal vein complex ( DVC ) affects blood loss , apical positive margins , and urinary control during robot-assisted laparoscopic radical prostatectomy ( RALP ) . OBJECTIVE To describe technique and outcomes for  athermal DVC division followed by selective suture ligation ( DVC-SSL ) compared with  DVC suture ligation followed by athermal division ( SL-DVC ) . DESIGN , SETTING S , AND PARTICIPANTS Retrospective study of prospect ively collected data from February 2008 to July 2010 for 303 SL-DVC and 240 DVC-SSL procedures . SURGICAL PROCEDURE RALP with comparison of DVC-SSL prior to anastomosis versus early SL-DVC prior to bladder-neck dissection . MEASUREMENTS Blood loss , transfusions , operative time , apical and overall positive margins , urine leaks , catheterization duration , and urinary control at 5 and 12 mo evaluated using 1 ) the Exp and ed Prostate Cancer Index ( EPIC ) urinary function scale and 2 ) continence defined as zero pads per day . RESULTS AND LIMITATIONS Men who underwent DVC-SSL versus SL-DVC were older ( mean : 59.9 vs 57.8 yr , p<0.001 ) , and relatively fewer white men underwent DVC-SSL versus SL-DVC ( 87.5 % vs 96.7 % , p<0.001 ) . Operative times were also shorter for DVC-SSL versus SL-DVC ( mean : 132 vs 147 min , p<0.001 ) . Men undergoing DVC-SSL versus SL-DVC experienced greater blood loss ( mean : 184.3 vs 175.6 ml , p=0.033 ) , and one DVC-SSL versus zero SL-DVC were transfused ( p=0.442 ) . Overall ( 12.2 % vs 12.0 % , p=1.0 ) and apical ( 1.3 % vs 2.7 % , p=0.361 ) positive surgical margins were similar for DVC-SSL versus SL-DVC . Although 5-mo postoperative urinary function ( mean : 72.9 vs 55.4 , p<0.001 ) and continence ( 61.4 % vs 39.6 % , p<0.001 ) were better for DVC-SSL versus SL-DVC , 12-mo urinary outcomes were similar . In adjusted analyses , DVC-SSL versus SL-DVC was associated with  shorter operative times ( parameter estimate [PE]±st and ard error [ SE ] : 16.84±2.56 , p<0.001 ) , and better 5-mo urinary function ( PE±SE : 19.93±3.09 , p<0.001 ) and continence ( odds ratio 3.39 , 95 % confidence interval 2.07 - 5.57 , p<0.001 ) . CONCLUSIONS DVC-SSL versus SL-DVC  improves early urinary control and shortens operative times due to fewer instrument changes with late versus early DVC control PURPOSE We identified the predictors of positive surgical margins in a series of patients undergoing robot assisted laparoscopic radical prostatectomy .  MATERIAL S AND METHODS We prospect ively collected data from 322 patients who underwent robot assisted laparoscopic radical prostatectomy for clinical ly localized prostate cancer between April 2005 and October 2008 , and who had not received any prior hormonal therapy .  RESULTS Positive surgical margins were observed in 95 cases ( 29.5 % ) . Specifically positive surgical margins were at the apex in 22 cases ( 6.8 % ) , anterior in 5 ( 1.6 % ) and posterolateral in 68 ( 21 % ) . Among the preoperative variables prostate volume on transrectal ultrasound  ( HR 0.42 
    Output:
    
Several surgeon-related characteristics or procedure-related issues may play a major role in PSM rates .
PSM rates are similar following RARP , RRP , and LRP .