***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 
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    Input: OBJECTIVES To compare intraoperative blood loss , perioperative hematocrit , and transfusion requirements in patients undergoing radical retropubic prostatectomy ( RRP ) versus robotic-assisted laparoscopic prostatectomy ( RALP ) by a single surgeon . METHODS During a 14-month period , 279 patients with localized carcinoma of the prostate were prospect ively enrolled in this comparative study . The decision of which surgical approach to use was by patient choice . Of the 279 patients , 176 underwent RALP and 103 underwent RRP . The serum hematocrit was obtained preoperatively and 24 hours postoperatively in all patients . The intraoperative blood loss was recorded , and transfusion requirements were noted . RESULTS Patients in the RALP group had significantly less intraoperative blood loss compared with the RRP group ( mean 191 mL versus 664 mL , P < 0.001 ) . Additionally , the difference in the discharge hematocrit ( 36.8 % versus 32.8 % , P < 0.001 ) and the mean perioperative change in hematocrit ( 8.0 % decrease versus 10.7 % decrease , P < 0.001 ) were significant between the RALP and RRP groups , respectively . Three patients in the RRP group ( 2.9 % ) and one in the RALP group ( 0.5 % ) required transfusion of blood products ( P = 0.14 ) . CONCLUSIONS The results of this study have shown that RALP is associated with less intraoperative bleeding than RRP , and patients undergoing RALP have a greater serum hematocrit at hospital discharge . The lack of a statistically significant difference in blood transfusion was partially attributable to the low transfusion rate in both groups in this series BACKGROUND Robot-assisted radical prostatectomy ( RARP ) is a widespread option for the treatment of patients with clinical ly localised prostate cancer . Modifications in the surgical technique may help to further improve functional outcomes . OBJECTIVE To assess the outcome of early catheter removal 48h after surgery , as opposed to st and ard catheter removal 6 d after surgery following RARP , using a newly developed surgical technique for posterior reconstruction and anastomosis ( Aalst technique ) . DESIGN , SETTING , AND PARTICIPANTS Patients scheduled for RARP were prospect ively scheduled for early catheter removal at postoperative d 2 ( group A , n=37 ) and st and ard catheter removal at postoperative d 6 ( group B , n=37 ) . SURGICAL PROCEDURE RARP was performed using the Da Vinci Si system . The Aalst technique for the urethro-vesical anastomosis including posterior reconstruction was used as previously described . OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The primary endpoint was spontaneous voiding after catheter removal . Secondary endpoints were rate of anastomotic urinary leakage after catheter removal , presence and severity of urethral , perineal , and abdominal pain , as well as patient 's bother after catheter removal using visual analogue scale ( VAS ) scores . Rate and severity of urinary incontinence after catheter removal were assessed using the International Consultation on Incontinence Question naire-Male Lower Urinary Tract Symptoms Module ( ICIQ-MLUTS ) question naire . RESULTS AND LIMITATIONS There was no significant difference between the groups with regard to baseline and perioperative parameters , as well as pathological features ; however , significantly more patients underwent bilateral nerve-sparing procedures in group A ( 34 vs 23 , p=0.008 ) . After catheter removal , patients in both groups showed spontaneous voiding , whereas only 11 % and 8 % of the patients in group A and group B experienced urinary retention after catheter removal ( p=0.7 ) . Patients in group B had significantly higher maximum flow rates , but lower voided volumes after catheter removal in comparison with patients in group A ( 21ml/s vs 10ml/s , p≤0.001 and 170ml vs 200ml , p≤0.001 , respectively ) . ICIQ-MLUTS question naire and VAS scores showed no significant differences between the groups at any time point . CONCLUSIONS The Aalst technique allows the removal of catheters 2 d after RARP and results in spontaneous voiding . Early removal showed no increased rate of urinary leakage , no negative impact on short-term continence and on perineal , urethral or penile pain , and no increase in urinary retention rates . Future studies have to confirm these results with longer follow-up including detailed parameters on return to daily activity . PATIENT SUMMARY We provide evidence that it is possible to remove the bladder catheter as early as 2 d after robot-assisted radical prostatectomy without any negative effects on voiding and pain parameters . Thus , leaving the hospital early without a catheter in place could represent a significant and relevant benefit for the patient PURPOSE Robotic assisted radical prostatectomy has largely replaced open radical prostatectomy for the surgical management of prostate cancer despite conflicting evidence of superiority with respect to disease control or functional sequelae . Using population cohort data , in this study we examined sexual and urinary function in men undergoing open radical prostatectomy vs those undergoing robotic assisted radical prostatectomy .  MATERIAL S AND METHODS Subjects surgically treated for prostate cancer were selected from 2 large population based prospect i ve cohort studies , the Prostate Cancer Outcomes Study ( enrolled 1994 to 1995 ) and the Comparative Effectiveness Analysis of Surgery and Radiation ( enrolled 2011 to 2012 ) . Subjects completed baseline , 6-month and 12-month st and ardized patient reported outcome measures . Main outcomes were between-group differences in functional outcome scores at 6 and 12 months using linear regression , and adjusting for baseline function , sociodemographic and clinical characteristics . Sensitivity analyses were used to evaluate outcomes between patients undergoing open radical prostatectomy and robotic assisted radical prostatectomy  within and across CEASAR and PCOS . RESULTS The combined cohort consisted of 2,438 men , 1,505 of whom underwent open radical prostatectomy and 933 of whom underwent robotic assisted radical prostatectomy .  Men treated with robotic assisted radical prostatectomy reported better urinary function at 6 months ( mean difference 3.77 points , 95 % CI 1.09 - 6.44 ) but not at 12 months ( 1.19 , -1.32 - 3.71 ) . Subjects treated with robotic assisted radical prostatectomy also reported superior sexual function at 6 months ( 8.31 , 6.02 - 10.56 ) and at 12 months ( 7.64 , 5.25 - 10.03 ) . Sensitivity analyses largely supported the sexual function findings with inconsistent support for urinary function results . CONCLUSIONS This population based study reveals that men undergoing robotic assisted radical prostatectomy  likely experience less decline in early urinary continence and sexual function than those undergoing open radical prostatectomy . The clinical meaning of these differences is uncertain and longer followup will be required to establish whether these benefits are durable Background To determine the effect of prostate weight on the preoperative and postoperative outcomes of robotic-assisted laparoscopic radical prostatectomy with a posterior approach to the seminal vesicle . Methods This retrospective study examined prospect ively collected data on 219 robotic-assisted laparoscopic radical prostatectomies performed from May 2011 to February 2013 . Patients were divided into four groups based on pathologic prostate weight : < 30 g , 30–49 g , 50–79 g , and ≥80 g. Continence and sexual function were assessed using vali date d question naires . Results Of the 219 patients , 19 , 143 , 51 , and 6 had prostates weighing < 30 g , 30–49 g , 50–79 g , and ≥80 g , respectively . Significant differences were found between the preoperative Gleason scores , total operative times , and robotic times of the groups . Both estimated blood loss and anastomosis time tended to be greater in the higher prostate weight groups , but the differences were not significant . No significant differences were observed in transfusion rate , length of catheterization , complication incidence , or positive surgical margins . The return of urinary function , as determined by question naire scores , was not affected by prostate weight . Conclusions Robotic-assisted laparoscopic radical prostatectomy can be performed safely and with similar perioperative outcomes , regardless of prostate weight . Indeed , oncological outcome , urinary continence , and complications were similar across the prostate weight groups , suggesting that robotic-assisted laparoscopic radical prostatectomy with a posterior approach to the seminal vesicle may be performed effectively on men with large prostates , despite greater surgical times Objectives To compare oncological outcomes of a consecutive retropubic radical prostatectomy ( RRP ) and robot-assisted radical prostatectomy ( RARP ) series performed by a single surgeon who had performed > 750 prior RRPs and was starting to perform RARPs . Material s and methods Prospect ively collected longitudinal data of 277 RRP and 730 RARP cases over a 5-year period were retrospectively analyzed . The RARP series were divided into 3 subgroups ( 1st , < 250 cases ; 2nd , 250–500 ; and 3rd , > 500 ) according to the surgical period . The positive surgical margin ( PSM ) and biochemical recurrence-free survival ( BCRFS ) rates were compared at each pathological stage . Results The pT2 PSM rates showed no significant difference between the RRP ( 7.8 % ) and RARP series ( 1st , 9.5 % ; 2nd , 14.1 % ; and 3rd , 9.8 % ) throughout the study period ( P = 0.689 , 0.079 , and 0.688 , respectively ) . Although the pT3 PSM rates of the 1st ( 50.6 % ) and 2nd RARP series ( 50.0 % ) were higher than that of the RRP series ( 36.0 % ; P = 0.044 and P = 0.069 , respectively ) , the 3rd RARP series had a comparable pT3 PSM rate ( 32.4 % , P = 0.641 ) . The 3-year BCRFS rates of the RRP and RARP series were similar at each pathological stage ( pT2 , 92.1 vs. 96.8 % , P = 0.517 ; pT3 , 60.0 vs. 67.3 % , P = 0.265 , respectively ) . Conclusions The pT2 PSM and short-term BCRFS rates were similar between RRP and RARP , and RARP showed comparable pT3 PSM rate with RRP after > 500 cases of surgical experience . Our data suggest that an experienced robotic surgeon at a high-volume center may achieve comparable oncological outcomes with open prostatectomy even in locally advanced disease OBJECTIVES Robotic assistance may enhance the precision of anatomic dissection and increase the feasibility of performing laparoscopic radical prostatectomy for most surgeons . We performed a prospect i ve comparison of 30 consecutive patients undergoing conventional radical retropubic prostatectomy ( RRP ) and 30 initial patients undergoing robot-assisted anatomic prostatectomy ( RAP ) at our institution . METHODS The study design was a prospect i ve nonr and omized comparison of anatomic RRP performed using the technique of Walsh and RAP performed with the da Vinci surgical system . We evaluated the baseline patient and tumor characteristics ( age , body mass index , serum prostate-specific antigen , Gleason score , and clinical stage ) , intraoperative parameters ( operative time , blood loss , and need for transfusion ) , postoperative parameters ( pain score , hospitalization duration , catheter duration ) , histopathologic parameters , and complications in the two groups . RESULTS The preoperative parameters were comparable for both groups of patients . The mean setup time for RAP was 0.95 hours . The mean operating time was 2.3 hours for RRP and 4.8 hours for RAP ( P < 0.001 ) . One patient required conversion from RAP to RRP because of a lack of progress . The mean blood loss was 970 mL for RRP and 329 mL for RAP ( P < 0.001 ) . The drop in hemoglobin was greater in the RRP group ( 4.4 versus 1.2 g in RAP ; P < 0.05 ) . The mean pain score on postoperative day 1 was 7 in the RRP group and 4 in RAP group ( P = 0.05 ) . The mean hospital stay was 56 hours in the RRP group and 36 hours in the RAP group ( P value not significant ) . Sixty-three percent of the RAP and 0 % of the RRP groups were discharged within 23 hours ( P < 0.001 ) . The mean duration of postoperative catheterization was 14 days for the RRP and 11 days for the RAP groups ( difference not significant ) . The pathologic stage , margin status , and prostate-specific antigen values were not different between the two groups . The setup time , operative time , blood loss amount , and catheterization duration were significantly reduced after the first 20 patients . CONCLUSIONS Currently , RAP is a longer procedure than RRP . However , the blood loss 
    Output:
    
Our results indicate that RARP appears to be safe and effective to its counterpart RRP in selected patients