since the initial description by walsh and donker in 1982 regarding the anatomic basis for erectile function , urologists have continuously explored technical advances that would improve both the oncologic and quality of life outcomes following radical prostatectomy . anatomical nerve - sparing methods have become mainstream practice with resultant improvements in erectile function rates following what was once considered a morbid procedure . although some interval modifications have been achieved in the radical retropubic prostatectomy operation , the next most significant advancement in surgical technique has been the introduction of laparoscopy . in the late 1990s , guillonneau and vallancien introduced laparoscopic radical prostatectomy as a viable surgical alternative for treating prostate cancer . subsequently , several centers have gone on to incorporate laparoscopic prostatectomy into their surgical armamentarium with successful outcomes . having set the stage for laparoscopy in the surgical treatment of prostate cancer , urologists then sought to improve upon such techniques with the use of robotics and the implementation of robotic radical prostatectomy . throughout the evolution of technology and treatment strategies , the urologic community has stringently emphasized the need to demonstrate both oncologic and therapeutic efficacy of procedures . the acceptance of changes in surgical technique has always been predated by demonstrable evidence from multiple institutions , regarding both the clinical and pathologic criteria that are essential for the successful treatment of prostate cancer . as such , we have entered the robotic age in the treatment of prostate cancer with encouraging reports from a few centers of excellence . here then , we hope to further diversify the experience in robotic prostatectomy and enrich the confidence of treating urologists by reporting our operative technique , oncologic and therapeutic outcomes , and learning curve from our initial series of over 140 consecutive patients treated by robotic radical prostatectomy . between january 2003 and may 2005 , 174 consecutive patients with clinically localized prostate cancer underwent a robotic radical prostatectomy performed by 2 surgeons ( dss and ds ) at the new york - presbyterian hospital . thirty - one patients with a follow - up period of less than 3 months were excluded from analysis in this study . all patients had biopsy proven adenocarcinoma of the prostate and were staged according to the 2002 american joint committee on cancer ( ajcc ) classification . all patients underwent a robotic radical prostatectomy with the da vinci surgical system ( intuitive surgical inc . , briefly , following induction of general endotracheal anesthesia , the patient was placed in the lithotomy position with a steep trendelenberg . the abdominal and groin areas were prepped and draped , intravenous antibiotics were administered before skin incision , and a 20-f , 30-cc urethral catheter was placed . a 1.5-cm incision was made to the left of the umbilicus , and a veress needle was used to insufflate the abdomen with co2 to a pressure of 15 cm h0 . a 10/12-mm trocar for the camera was placed at the umbilicus , two 8-mm trocars for the robotic arms were placed just lateral to the medial umbilical ligaments , a 5-mm suction port was introduced to the right of the umbilicus , and 10/12-mm and 5-mm trocars were introduced 2 fingerbreadths above the iliac crest on the patient 's right and left side , respectively . overall , 6 ports were used , and the da vinci robot was docked . starting with a 30 angle - up lens , the medial umbilical ligaments were incised up the anterior abdominal wall allowing cephalad reflection of the bladder and entry into the space of retzius . the lens was changed to a 0 angle , and the endopelvic fascia was opened in a cautery - free manner to expose the apex of the prostate . the levator muscles were swept posterolaterally , and the puboprostatic ligaments were sharply divided to gain further length beyond the apex of the prostate . the superficial and deep dorsal veins were ligated with a 0-vicryl stitch , and a second 0-vicryl stitch was then placed for back bleeding over the anterior surface of the prostate . the anterior bladder neck was divided , and the ureteral orifice position and presence of a median lobe were assessed , and then the posterior bladder neck was divided . the vasa were divided and the seminal vesicles were dissected in a cautery - free manner to avoid potential injury to the neurovascular bundles . the posterior layer of denonvillier 's fascia was divided allowing for identification of perirectal fat , which served as a guide between the prostate and rectum . to optimize nerve sparing , all prostatic pedicles were clipped and sharply divided without using electrocautery . the lateral prostatic fascia was incised on each side allowing the neurovascular bundles to fall posterolaterally , and a bilateral nerve - sparing procedure was performed when possible . the neurovascular bundle was released distally to the level of the urethra and prostatic apex . at this point , the only remaining attachments of the prostate were the dorsal vein complex ( dvc ) and the urethra . the dvc and urethra were then divided rendering the prostate free , and the specimen was placed in a 10-mm endocatch bag . intraoperative frozen sections was used judiciously to help decrease the incidence of positive surgical margins . the urethrovesical anastomosis was performed in a running fashion by using a double - arm 2 0 monocryl suture . an 18-fr , 10-ml urethral catheter was placed and irrigated to ensure a water - tight anastomosis . a bilateral pelvic lymph node dissection was performed following completion of the urethrovesical anastomosis in patients with a greater than 2% chance of positive lymph nodes as obtained from the partin predictive tables . borders of the node dissection were the external iliac vein anteriorly , obturator nerve posteriorly , bifurcation of common iliac artery superiorly , and cooper 's ligament inferiorly . a # 10 flat jp drain was placed into the pelvis and brought out through the left - side 5-mm port . the da vinci robot was then undocked , all trocars were removed under direct vision , and the specimen was removed through the camera port . the fascia at the extraction site was closed with a 2 0 vicryl suture , and all skin incisions were closed with a 4  0 biosyn stitch . postoperative psa values , urinary continence , and erectile function were evaluated 6 weeks postoperatively , every 3 months for the first year , every 6 months for the second year , and yearly thereafter . before surgery , all men were evaluated with the following data recorded : age , bmi , clinical t stage , biopsy gleason score , and prostate - specific antigen ( psa ) . operative outcome measures included operative time , estimated blood loss ( ebl ) , and complications . postoperative outcomes were length of hospital stay , catheter time , pathology , margin status , biochemical recurrence , and return of continence . the chi - square (  ) log - rank test with the yates correction factor and the unpaired 2-tailed student t test were used to compare variables between the first and second 70 patients in our series . between january 2003 and may 2005 , 174 consecutive patients with clinically localized prostate cancer underwent a robotic radical prostatectomy performed by 2 surgeons ( dss and ds ) at the new york - presbyterian hospital . thirty - one patients with a follow - up period of less than 3 months were excluded from analysis in this study . all patients had biopsy proven adenocarcinoma of the prostate and were staged according to the 2002 american joint committee on cancer ( ajcc ) classification . all patients underwent a robotic radical prostatectomy with the da vinci surgical system ( intuitive surgical inc . , sunnyvale , ca ) . briefly , following induction of general endotracheal anesthesia , the patient was placed in the lithotomy position with a steep trendelenberg . the abdominal and groin areas were prepped and draped , intravenous antibiotics were administered before skin incision , and a 20-f , 30-cc urethral catheter was placed . a 1.5-cm incision was made to the left of the umbilicus , and a veress needle was used to insufflate the abdomen with co2 to a pressure of 15 cm h0 . a 10/12-mm trocar for the camera was placed at the umbilicus , two 8-mm trocars for the robotic arms were placed just lateral to the medial umbilical ligaments , a 5-mm suction port was introduced to the right of the umbilicus , and 10/12-mm and 5-mm trocars were introduced 2 fingerbreadths above the iliac crest on the patient 's right and left side , respectively . overall , 6 ports were used , and the da vinci robot was docked . starting with a 30 angle - up lens , the medial umbilical ligaments were incised up the anterior abdominal wall allowing cephalad reflection of the bladder and entry into the space of retzius . the lens was changed to a 0 angle , and the endopelvic fascia was opened in a cautery - free manner to expose the apex of the prostate . the levator muscles were swept posterolaterally , and the puboprostatic ligaments were sharply divided to gain further length beyond the apex of the prostate . the superficial and deep dorsal veins were ligated with a 0-vicryl stitch , and a second 0-vicryl stitch was then placed for back bleeding over the anterior surface of the prostate . the anterior bladder neck was divided , and the ureteral orifice position and presence of a median lobe were assessed , and then the posterior bladder neck was divided . the vasa were divided and the seminal vesicles were dissected in a cautery - free manner to avoid potential injury to the neurovascular bundles . the posterior layer of denonvillier 's fascia was divided allowing for identification of perirectal fat , which served as a guide between the prostate and rectum . to optimize nerve sparing , the lateral prostatic fascia was incised on each side allowing the neurovascular bundles to fall posterolaterally , and a bilateral nerve - sparing procedure was performed when possible . the neurovascular bundle was released distally to the level of the urethra and prostatic apex . at this point , the only remaining attachments of the prostate were the dorsal vein complex ( dvc ) and the urethra . the dvc and urethra were then divided rendering the prostate free , and the specimen was placed in a 10-mm endocatch bag . intraoperative frozen sections was used judiciously to help decrease the incidence of positive surgical margins . the urethrovesical anastomosis was performed in a running fashion by using a double - arm 2 0 monocryl suture . an 18-fr , 10-ml urethral catheter was placed and irrigated to ensure a water - tight anastomosis . a bilateral pelvic lymph node dissection was performed following completion of the urethrovesical anastomosis in patients with a greater than 2% chance of positive lymph nodes as obtained from the partin predictive tables . borders of the node dissection were the external iliac vein anteriorly , obturator nerve posteriorly , bifurcation of common iliac artery superiorly , and cooper 's ligament inferiorly . a # 10 flat jp drain was placed into the pelvis and brought out through the left - side 5-mm port . the da vinci robot was then undocked , all trocars were removed under direct vision , and the specimen was removed through the camera port . the fascia at the extraction site was closed with a 2 0 vicryl suture , and all skin incisions were closed with a 4  0 biosyn stitch . postoperative psa values , urinary continence , and erectile function were evaluated 6 weeks postoperatively , every 3 months for the first year , every 6 months for the second year , and yearly thereafter . before surgery , all men were evaluated with the following data recorded : age , bmi , clinical t stage , biopsy gleason score , and prostate - specific antigen ( psa ) . operative outcome measures included operative time , estimated blood loss ( ebl ) , and complications . postoperative outcomes were length of hospital stay , catheter time , pathology , margin status , biochemical recurrence , and return of continence . the chi - square (  ) log - rank test with the yates correction factor and the unpaired 2-tailed student t test were used to compare variables between the first and second 70 patients in our series . the mean operative time was 241 minutes ( range , 120 to 540 ) , with a decrease of over 100 minutes when comparing our initial series of 70 with our more recent 70 patients ( 318 vs 209 , p<0.001 ) . the mean estimated blood loss ( ebl ) was 274 ml ( range , 10 to 800 ) , with a significant decrease in our more recent series of patients ( 387 vs 155 , p<0.001 ) . in 127 men , data regarding nerve sparing were available . one hundred and nine of 127 men ( 86% ) had a bilateral nerve - sparing operation , whereas 13/127(10% ) had unilateral nerve - sparing , and 5/127(4% ) had bilateral nerve resections . sixty - six of the last 70 patients ( 94% ) had bilateral nerve - sparing operations . five patients ( 3% ) had a conversion to open surgery for bleeding , large intravesical median lobes , adherence to the rectum , and robot malfunction . of our most recent 70 patients , 65 ( 93% ) were discharged within 24 hours of surgery . the urethral catheter was removed at a mean time of 8.9 days ( range , 1 to 29 ) . at a mean follow - up of 11 months , 96% of patients ( 137/143 ) had a psa<0.2 ng / ml . four patients had postoperative complications including an ileus , small bowel obstruction1 requiring reoperation , and a urethral stricture requiring repeat dilatation . two patients ( 1% ) did not have any tumor identifiable in the final pathology specimen , 1 of whom received preoperative hormonal deprivation therapy . organ - confined ( oc ) disease ( pt2 ) was present in 122/141 patients ( 87% ) and extracapsular extension ( ece ) was present in the final pathology analysis ( pt3/t4 ) of 19/141 ( 13% ) patients . twenty - four of 141 men ( 17% ) in our series had a positive margin on examination of the specimen , with a decrease from 23% ( 16/70 ) to 11% ( 8/70 ) when comparing our more recent 70 patients with the initial 70 ( p=0.07 ) . patients with ece had a significantly higher rate of positive surgical margins than did those with oc disease ( 47% vs 12% , p<0.001 ) . when exclusively considering pt3 disease , we further noted a decrease in positive margins when comparing our first 70 patients ( 5/9 ; 56% ) with our latter 70 ( 2/8 ; 25% ) . no significant difference existed in positive margin rates in the gleason 7 cohort ( 19/122 , 16% ) and the gleason > 7 group ( 4/19 , 21% ) ( p=0.55 ) . over 40% ( 14/33 ) of the positive margins the number of positive apical , anterior , and posterior positive margins remained unchanged as experience matured in this series ; however , margin positivity at the bladder neck decreased from 7 in the first cohort of patients to 2 in our latter operative experience . patients requiring no urinary pads were considered continent , and the use of even one pad per day for occasional stress urinary incontinence was not considered continent for the purposes of our analysis . the median time to complete continence was 3.5 months , and over 95% of patients were fully continent at 1-year follow - up . because our data are awaiting maturity , we will hold off on reporting potency data in this analysis . as robotic surgery becomes a more accepted treatment modality for clinically localized prostate cancer , many urologists are struggling to incorporate this technique into their therapeutic armamentarium . increasingly , surgeons are foregoing open retropubic approaches with a technically challenging robotic - assisted technique for which efficacy data are currently limited but growing . it is the intent of our analysis to objectively analyze the robotic approach from an oncologic standpoint , and in doing so , to characterize the oncologic and therapeutic efficacy of this relatively new and growing technology . although the ultimate measure of any intervention is the ability to prolong long - term survival , modifications in surgical technique can be assessed in the short - term by analyzing pertinent oncological principles . one such variable is pathology margin status . it is generally agreed that a positive margin is indicative of incomplete tumor resection and bears significant prognostic importance . several institutions have demonstrated the independent prognostic significance of positive surgical margins across all stages of disease . han et al further point out that the rate of positive surgical margins has declined dramatically from around 40% during the early 1980s to less than 10% more recently . although these observations are likely multifactorial , the lower positive margin rates over the past decade are largely attributable to the stage migration that has occurred in the era of psa screening . it is imperative , however , to also consider contemporary refinements in preoperative planning , biopsy strategies , and surgical technique . as we embark on the robotic age for the treatment of prostate cancer , it is essential that we adhere to surgical principles learned over the last 3 decades . in this study , we report an overall positive margin rate of 17% . during the first half of our experience , we noted a 23% positive margin rate , which declined to 11% over our last 70 consecutive patients . further , no difference existed in the pathologic distribution of tumors between our initial 70 patients and our latter 70 ( 9 vs 10 cases of ece ) . collectively , these data suggest that the decline in the positive margin rate is most attributable to an improved surgical skill set in the robotic technique rather than a decrease in the number of biologically aggressive tumors . subset analysis of the data also notes a significantly lower incidence of positive margins when comparing specimens with organ - confined disease with those with extracapsular extension ( 12% vs. 47% , p<0.001 ) . noteworthy , however , is the decrease in positive margin rates from 56% to 25% in the pt3 subgroup of tumors during the evolution of our experience . this underscores that robotic prostatectomy is a reasonable surgical alternative for organ - confined , as well as pt3 disease . thus , even in our initial robotic experience , the results compare favorably with those of other reported robotic series , as well as with the current oncologic gold standard open retropubic approach . the specific location of positive margins is explainable both by surgical experience and technique . as depicted in table 4 , bladder neck positive margins declined over 3-fold when comparing the first half of our robotic experience and our most recent surgical series . the antegrade approach utilized during a robotic prostatectomy can be quite challenging and choosing the appropriate location for incision of the bladder neck can be difficult . as our experience in robotic surgery has matured , we have learned to take a wider bladder neck and robotically reconstruct the bladder as necessary . this modification has probably resulted in decreased positive bladder neck margins as our experience increased . in terms of the anterior and apical margins , we noted that 15% ( 5/33 ) of all positive margin sites were at each of these 2 anatomic locations , respectively . this compares favorably with other published reports in which the apical positive margin rates range from 5% to 28% . we believe that the anterior and apical dissection is enhanced with the robotic approach likely due to the use of an angled lens resulting in improved visualization of the dorsal vein / urethral complex . at 1-year follow - up , 97% ( 139/143 ) of men were fully continent without the requirement of any pads . our 3-month follow - up data , however , indicate that less than 50% of patients are fully continent at this time point . anecdotally , this is lower than the continence rates we have observed for our contemporary open retropubic prostatectomy series . one possible explanation is that the enhanced robotic visualization may result in excessive dissection of the striated sphincter complex beyond the apex of the prostate . to improve the early continence rates , we have made several modifications in our current technique including tacking the urethra to the periosteum of the pubis and avoiding excessive dissection beyond the apex of the prostate . with such modifications , our short - term continence rates have improved in a more contemporary group of patients ( data not shown ) . robotic - assisted radical prostatectomy is an effective modality for the treatment of clinically localized prostate cancer . we acknowledge that a learning curve needs to be overcome ; however , with a rigorous , focused robotic educational program , early oncologic functional results compare favorably with results of the open retropubic approach .
objective : to report the operative technique , oncologic and therapeutic outcomes , and learning curve from our initial series of over 140 patients treated by robotic radical prostatectomy.methods:between january 2003 and may 2005 , 143 patients with clinically localized prostate cancer underwent a robotic radical prostatectomy . 
 prospective data collection included patient age , body mass index ( bmi ) , clinical t stage , biopsy gleason score , and prostate - specific antigen ( psa ) . 
 operative outcome measures included operative time , estimated blood loss ( ebl ) , and complications . 
 postoperative outcomes were length of hospital stay , catheter duration , pathology , margin status , biochemical recurrence , and return of continence.results:mean operative time was 241 minutes with an ebl of 274 ml . 
 five patients ( 3% ) required conversion to open surgery . 
 the average hospitalization was 1.8 days , and foley catheters were removed after 8.9 days . 
 twenty - four of 141 men ( 17% ) had a positive surgical margin , with a decrease from 23% in the first half of our experience to 11% in the latter half . 
 patients with an extracapsular extension had a significantly higher positive surgical margin rate than did those with organ - confined disease ( 47% vs 15% ) . over 40% of the positive margins 
 were located posteriorly . at a mean follow - up of 11 months 
 , 96% of patients had a psa<0.2 ng / ml . the median time to complete continence was 3.5 months , and over 95% of patients were fully continent at 1 year.conclusion:robotic radical prostatectomy is an effective treatment modality for clinically localized prostate cancer . 
 although a learning curve needs to be overcome , patients experienced benefits in convalescence with early oncologic and functional outcomes comparable to those of the open approach . 
 longer - term results are needed ; however , patient outcomes in our series are encouraging .