Deliu Victor Matei, Department of Urology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy. e-mail: email@example.com
Study Type – Therapy (case series)
Level of Evidence 4
What's known on the subject? and What does the study add?
The open simple prostatectomy (OSP) is the ‘gold standard’ for high-volume prostate adenomas. It shows very good functional results despite its invasiveness. Minimally invasive approaches, e.g. laparoscopy or holmium laser enucleation of the prostate, have been ‘tested’ but none have proved a substitute for the OSP.
The robot-assisted approach provides optimal functional results and is easy to perform for experienced robotic surgeons. Extending the indication of robotics to low-incidence pathologies can take advantage of the opportunity to ‘see the procedure’ using available information technology, e.g. Youtube™ that presents as an unexpectedly useful tool.
• To evaluate the outcome, feasibility and reproducibility of a robot-assisted (RA) approach for simple prostatectomy (SP) in cases of high-volume symptomatic benign prostatic hyperplasia (HVS-BPH).
PATIENTS AND METHODS
• In all, 35 consecutive patients underwent RASP for HVS-BPH using a previously described technique.
• The mean prostate volume on preoperative transrectal ultrasonography was 106.6 mL.
• All but two patients (with bladder calculi) had an adenoma volume of >65 mL and 27 (77.1%) >80 mL. Nine patients (25.7%) had an indwelling catheter.
• The mean International Prostate Symptom Score (IPSS) was 28.
• The median operative duration was 180 min and the mean hospital stay was 3.17 days.
• The mean catheter duration was 7.4 days and discontinuous or continuous catheter irrigation was required in two and seven patients, respectively (25.1%).
• In all, 10 patients (28.6%) had practically no blood loss. No patients had a transfusion.
• The mean postoperative peak urinary flow was 18.9 mL/s (P < 0.001), while the mean IPSS was 7 (P < 0.001).
• For costs, while superficially RASP appeared more expensive than open SP (OSP), when considering the higher costs of hospitalisation for OSP, RASP was cheaper. Also, bipolar-TURP costs in patients with large-volume prostates had rather similar costs to RASP.
• RASP is a feasible and reproducible procedure with outcome advantages when compared with the open or with other minimally invasive techniques (laser or laparoscopy). As a result, a RA approach is worth considering in cases of high-volume prostate adenomas.
• Extending the indication of the RA approach, to the SP, requires firstly that the surgeon be proficient in RA surgery and secondly that as the incidence rate of HVS-BPH is low, the surgeon has had the opportunity to ‘see the procedure’.
For many years open simple prostatectomy (OSP) has been the primary treatment option for patients with prostate enlargement due to BPH [1–6].
The reproducibility and the low invasiveness of TURP resulted in a worldwide expansion of this technique limiting the indications for open prostatectomy to the treatment of adenomas of >80–100 mL, especially if coexistent pathological conditions (i.e. calculi, diverticula, etc.) were present. In fact, for these patients, OSP seems to be more effective and safer than TURP .
Nevertheless, looking at historical and more recent series [1–7] one notices that, while open prostatectomy is more invasive and requires a lower midline incision with subsequently longer hospitalisation and convalescence than transurethral techniques, it results in an excellent functional outcome and low re-operation rates [1–8].
The above mentioned disadvantages in addition to higher blood losses and thus, higher transfusion rates, commonly reported in OSP series [2,7,8] have determined an effort to find and develop minimally invasive approaches to the procedure.
The aim of the present study was to present our experience and to argue for the use of a robot-assisted (RA) approach in performing SP.
PATIENTS AND METHODS
From March 2009 to March 2011, 35 patients underwent RASP for high-volume symptomatic BPH (HVS-BPH). In two cases prostatic volume was <80 mL, but there were concomitant multiple bladder stones. The procedures were performed successively in two hospitals: cases 1–20 using a daVinci™ three-arm Standard System (Saint Joseph Hospital, Milan, Italy) and cases 21–35 using a 4S HD or an Si System (IEO). The diagnostic evaluation consisted of physical examination and IPSS evaluation, uroflowmetry (excepting the nine patients with an indwelling catheter) and volumetric suprapubic ultrasonography (US). The upper urinary tract was assessed by serum creatinine and renal US. In all, 12 patients had undergone prior prostatic biopsy. At 1 month after surgery the PSA level and IPSS were determined, and a physical examination and uroflowmetry performed. The chi-squared test was used for statistical analysis of preoperative vs postoperative uroflowmetry and IPSS data.
We performed the RASP according to the technique previously described by Sotelo et al. . With the patient under general anaesthesia and in a steep (25 °) Trendelenburg position, pneumoperitoneum was obtained, generally using a Veress needle inserted in the left hypocondrium, where the risk of bowel adhesions is low and where the parietal peritoneum seems to be more adherent to the posterior layer of the rectus muscle sheath. A transperitoneal approach was used with a port configuration similar to that described by Patel et al.  for the daVinci™ radical prostatectomy (RP), excluding the 5-mm assistant port, using thus only five trocars: 12 mm for the optic, two (if Standard System was used: cases 1–21) or three (if 4S System was used) 8-mm robotic trocars, and a 12-mm assistant port in the supra-iliac right position. If the daVinci™ Standard System was used, instead of the left supra-iliac robotic port, a 5-mm assistant port was placed. We used the 0 ° optic, one monopolar scissors, one plasma-kinetic PK® forceps and one large needle driver. If the daVinci™ 4S System was used, an additional Cadhiere Prograsp forceps was used.
After the incision of the urachus and the umbilical arteries, the bladder was detached from the abdominal wall and the space of Retzius was developed until the anterior surface of the prostate was cleaned from overlying fatty tissue. A horizontal cystotomy incision was performed immediately proximally to the junction of the bladder and prostate, some millimetres cranially with respect to the incision commonly performed during the RP. The bulging prostatic lobes (with or without a median lobe) were then visualised. A circular incision was made on the bladder mucosa overlying the prostate lobes at the level of the bladder neck, as in the open approach, in order to find and successively develop the cleavage plane of the adenoma. A suture was placed into the median lobe to help traction during the dissection (using a needle driver from the left 5-mm assistant port if the Standard System was used, or the Cadhiere grasp on the third arm, in the case of the 4S daVinci™ System). The adenoma was freed from the prostatic pars periferica by using a combination of electrocautery and blunt dissection. Any perforating blood vessel was controlled with the plasma-kinetic bipolar (PK®) or monopolar coagulation. At the end, after having also freed the apex of the prostate, the urethra was incised clearly proximally with respect to the external sphincter, to avoid its damage. The prostatic fossa was then ‘trigonized’ according to the technique described by Sotelo et al.  by suturing the posterior edge of the bladder neck mucosa to the posterior edge of the urethra. If bleeding at the level of the prostatic fossa persisted, haemostatic matrix agents (Floseal™, Tacoseal™) were placed in contact with the prostatic pars periferica. A 24 F Simplastic Plus™ catheter was inserted with the balloon into the bladder. The horizontal cystotomy incision was closed in a watertight manner using a 2/0 monofilament running suture and the bladder was irrigated to assess repair integrity. A drain was inserted. The prostate adenoma was extracted using an EndoCatch™ bag.
There was no continuous irrigation of the catheter unless there was significant postoperative haematuria (seven cases i.e. 20%). Short term antibiotic prophylaxis (cephazolin 2 g, 30 min preoperatively and 1 g, 12 h postoperatively) was given. If haematuria was judged clinically insignificant, patients were discharged 2 days after surgery with an indwelling catheter and without drainage. The catheter was removed 7 days (cases 1–23) or 5 days (cases 24–35) after surgery.
In all, 35 RASP were performed using this technique with no open conversions. The clinical data are given in Table 1.
Table 1. Epidemiology and clinical data of the present series
Operative duration, min
Blood loss, mL
PSA concentration, ng/mL
US prostate volume, mL
Prostate weight, g
Qmax (normalised) preoperative, mL/s
Qmax (normalised) postoperative, mL/s
The mean (range) prostate volume on preoperative TRUS was 96.2 (37–240) mL. All but two patients (having bladder calculi) had an adenoma volume of >65 mL and 27 (77.1%), >80 mL. Nine patients (25.7%) had an indwelling catheter. The mean IPSS was 28. The mean PSA concentration was was 5.44 ng/mL; 18 patients had a PSA concentration of >4 ng/mL and 12 (34.3%) underwent at least one biopsy either for the PSA level or for its kinetic (i.e. velocity).
The median (range) operative duration was 180 (134–300) min, the mean (range) hospital stay was 3.17 (2–9) days while the mean (range) Foley catheter duration was 7.4 (5–14) days. Discontinuous (using a Guyon syringe) or continuous catheter irrigation was required in two and seven patients, respectively (25.1%). In all, 10 patients (28.6%) had practically no blood loss (conventionally considered 10 mL). No patient received transfusion.
The drain was removed 1 day after surgery, except in three cases.
Pathology confirmed benign glandular-stromal hyperplasia in all but one patient (with a pT1a adenocarcinoma). The mean specimen weight on pathological examination was 87 g. The average amount of removed tissue was 81.2% and the median was 68.6%. In patients with a prostate volume of ≥100 mL, the mean amount of removed tissue was 91%, while in the group of patients with a prostate volume of <100 mL but ≥80 mL mean amount of removed tissue was 88%.
The mean postoperative normalised maximum urinary flow rate (Qmax; calculated as: Qmax measured*√200/voided volume + residual urine) was 18.9 mL/s, while the mean IPSS was 7 (both P < 0.001).
The benefits of the RA approach in urological surgery are mainly advocated (even if strongly debated, too) for the RP and defined by the ‘trifecta’. In fact, during the last few years, the focus of the urological community has been to highlight and to prove (if possible) a presumed (and desired) superiority of this approach over the traditional open one, in the absence of prospective randomised studies.
Extending the indication of this approach, to the SP, might encounter resistance mainly due to the worldwide expansion of the endoscopic TURP technique (a rather strong competitor)  and to the high costs of the RA procedures . However, in our view, several points need to be considered.
When a surgical solution is chosen for patients with obstructive urinary symptoms, different parameters are evaluated to select the most appropriate approach, which will allow the best results. Among these, in our opinion and in our clinical practice prostate volume plays a major role.
Assuming that TURP is the main indication for obstructive, benign, low-volume (<60–80 mL) [7,8,11] BPH, the situation may change if high-volume (i.e. ≥80–100 mL) BPH is considered [2–8]. For these patients (and moreover, if other pathological conditions, e.g. bladder stones, large diverticula, etc., coexist) OSP is indicated, as it seems to be more effective and safer than TURP . The AUA and European Association of Urology guidelines too, suggest that open surgery should be the therapeutic choice when prostate volume is >80 mL.
However, one might advocate that bipolar-TURP is the real competitor of the RASP even in cases of high prostatic volume, primarily due to the quicker resection.
We retrospectively considered patients having undergone bipolar-TURP in our Division since 2007 (using the TURis system; Olympus, Japan) presenting a preoperative US volume of >70 mL. In all, 42 patients met this criterion. From these, 17 were excluded, as the resected volume was <35 mL. In the remaining series of 25 patients the mean (range) TRUS volume was 93.4 (70–150) mL, while the mean volume of tissue removed was 63.8 mL, accounting for 68.3% of the initial prostate volume. When considering separately patients with prostate volumes of <80 mL, 81–99 mL and >100 mL, the percentage of prostatic tissue removed decreased from 71.2% to 69% to 66.5%, respectively. The mean operative duration was 106 min, hospitalisation was 4.2 days, while catheterisation duration was 4.12 days; three patients had a transfusion. The main problem emerging from this short retrospective review of our prostate TURis series is that the larger the prostate volume, the higher the risk of leaving residual tissue, with the resultant increased risk of having a relapse of the symptoms. In 52/132 patients with a prostate volume >80 mL (mean 101.6 mL), Zhu et al.  reported an operative duration of 96.06 min, slightly lower than ours, due in our opinion to the use of the plasmakinetic Gyrus System that has a larger resection loop than Olympus TURis System. The resected tissue in that subgroup was 64.75% of the initial measured volume. The catheterisation and hospitalisation times were also similar to the present series, at 3.44 and 6.23 days, respectively. Ou et al.  reported similar results in their series of 69 patients, the TURP procedure was not faster than OSP and again, only 53.2% of prostatic tissue was resected in the TURP group compared with 84.4% in the OSP group. Comparing the present series of TURis and OSP (16 procedures) performed during the same period, even though the mean preoperative prostate volume was significantly higher in the second group (145 vs 93.4 mL) the procedure time was shorter at 93 vs 106 min and the relative amount of tissue being removed was higher (75.6% vs 68.3%, if all the patients in both series were considered and 76.8% vs 66.5% if only the cases with ≥100 mL prostate volume were considered). So, even if retrospective and biased by our preference for OSP rather than TURis for high-volume prostates, the present data, considering bipolar-TURP vs OSP, confirm the results of randomised trial of Ou et al. .
When considering the patients in the RASP series, the relative amounts of removed tissue was higher, both when mean values (81.2% for RASP vs 75.6% for OSP and 70.4% for TURis) and median values were considered (68.6% for RASP vs 65.7% for OSP and 66.7% for TURis).
To have a comprehensive overview about the features and outcomes of OSP and of the patients undergoing OSP, we reviewed publications from 1995 to present and found 14 relevant papers. Most of the series were comparative: OSP vs TURP, laser or laparoscopic procedures. There were only seven ‘only-OSP’ series and very few (i.e. four) prospective randomised comparative studies (Table 2) [1–3,5–8,14–20]. However, it seems apparent that the OSP has well-recognised advantages (i.e. optimal functional results, short operation time [mean 82.3 min], low re-operation rates; no TURP syndrome) that are primarily overshadowed by its disadvantages of longer catheterisation time (5.76 days), need of longer catheter irrigation time, higher blood loss leading to higher transfusion rates (mean 11.3%, range 4.4–17.9%). These features translate in longer hospital stays (mean 7.61 days) and, consequently longer convalescence. Incidence rates of open prostatectomy in developed countries are 12–40% (in Italy, 29–32%) [2–6].
For these reasons, TURP is not an optimal choice for large-volume obstructive prostates [7,21], so different minimally invasive approaches have been proposed, e.g. holmium laser enucleation of the prostate (HoLEP), laparoscopic and, recently, RA adenomectomy.
HoLEP is as safe and effective as TURP for mean prostate volumes of >40 and >70 mL according to Naspro et al.  and Wilson et al. , respectively, and also appears to be an attractive solution for large (>100 mL) prostates [14,15], with results comparable with open surgery. Conversely, although it requires a shorter catheterisation time, operative time is longer than other conventional techniques (74–135 min for adenomas of 40–83 g) [14,15]. Despite laser treatment producing promising results it is still only performed in a few centres.
For years, laparoscopy has shown a continuous widening of its application field in the urological surgery domain. There is no doubt that the development of laparoscopic RP has influenced the approach to SP.
The first laparoscopic SP was reported in 2002 by Mariano et al. . Since then, published series of laparoscopic SP [18,19,24–33] increased almost every year until 2008 (when the first report of RASP was published) and then it declined (Fig. 1). Reviewing publications from 2003 to date, 12 papers were considered (including five comparative vs OSP and four prospective) and some general observations about laparoscopic SP can be made (Table 3) [18,19,24–33]. Faced with a clearly longer procedure time (122 min) compared with other types of procedure, there is a decline in hospitalisation (mean 4.78 days) and catheterisation times (mean 3.52 days) and particularly in transfusion rate (mean 5.46%) for the minimally invasive approach.
Table 3. Laparoscopic SP: data from published series
Looking at these papers in depth, apart from the classic data (reported above and comparable with those from the OSP series), new information emerges, to further justify the laparoscopic (i.e. minimally invasive) approach.
Firstly, many authors report a reduction in the operative duration as the number of procedures performed increases, showing an inverse relationship between operative duration and surgeon experience, probably reflecting an improvement in laparoscopic skills (Table 4) [9,18,19,25,28,29,33].
Many authors emphasise the role of the incidence view due to the position of the optic system allowing a better ‘vascular control [due to] improved visualization’ and also a ‘direct visual monitoring which enabled selective coagulation and an excellent joining of the capsule’.
Moreover, many of these papers indicate the low analgesic drugs use, even if there is no uniformity in the reporting of these data (mg/patient, days of analgesic therapy, use or not of opioids).
Finally, laparoscopy seems to enable a low rate of continuous catheter irrigation. In fact, Massoud et al.  entitled his poster presented at the Société Internationale d'Urologie Congress (September 2007): ‘Transvesico-prostatic approach of laparoscopic simple prostatectomy (LSP): novel technique avoiding postoperative bladder irrigation’.
We can conclude that the laparoscopic approach presents for patients all the advantages derived from its minimal invasiveness (i.e. low pain, reduced blood loss and transfusion rates), resulting in shorter hospitalisation and convalescence than for OSP. Some concerns persist about the costs and procedure duration, but as previously mentioned, these are supposed to improve with time due to the refinement of the surgeon's laparoscopic experience.
Considering the surgeons viewpoint, the laparoscopic approach allows better vision due to image magnification and an almost bloodless field due to the pneumoperitoneum. However, the flat (two-dimensional) vision, with only three-degrees of freedom for instrument movement and prolonged standing and uncomfortable operating position are important disadvantages determining long learning curves and afterwards, slow refinement of laparoscopic skills.
Since 2008, six series of RASP have been published (Table 5) [9,34–38] comprising 59 patients, excluding three finger-assisted procedures . We analysed the data, including the update (+20 patients) of the present series (overall 79 patients). One instantly notices that the mean operative duration is extended further, while the hospital stay (2.65 days) and the need of transfusion (3.79%) decline. However, an important bias is that these are initial results and the series are rather small. In our experience the skin-to-skin operative duration decreased from 300 min to 134 min, and the same results were reported by Sotelo et al.  and John et al.  (in patients undergoing pure RA adenoma enucleation).
It was quite difficult to precisely assess and correctly evaluate the operative duration, as the first steps of the procedure and the final bladder suture were generally performed (after the seventh procedure) by young urologists during their training in RA surgery. However, the data show a slowly decreasing procedural time with a tendency line with a hypothetical gain of 1.1 min after each procedure (Fig. 2).
Beyond these considerations, the advantages of RASP for the patient assume all the advantages of a minimally invasive approach, as previously discussed for the laparoscopic approach. John et al. reported an average time of ‘return to work’ of 13 days.
For the surgeon, in contrast, the advantages are consistent. The often advocated three-dimensional vision, the Endowrist™ technology and the more ergonomic position during the procedure (i.e. seated) make the procedure easier to perform than in laparoscopy and also, easier to learn.
There are two key factors influencing the implementation of RASP for the surgeon. Firstly, the urologist has to have had completed his robotic learning curve by performing an adequate number of RP procedures. After having attained good robotic skills, it is only natural for the surgeon to extend the indications for which he/she uses their skills. The author performed his first RASP after >100 RARPs. The second key factor, especially for pathologies with well-known lower incidence rates than prostatic cancer (e.g. high-volume prostate hyperplasia), is the possibility using information technology to ‘see the procedure’ and not only to ‘read a description about it’ or ‘see drawings describing the main stages’. In this context, Youtube™ has become a very unexpected and useful tool.
Finally, there are some considerations about the costs. Lotan et al.  reported a $1726 (American dollars) higher cost of RA laparoscopic prostatectomy (RALP) than for open RP. Other authors reported costs range from $3441 to $5496 for RALP [40–42]. Finally, a recent review , pointed out that RALP is $2315 more expensive  than open RP, not only for the higher overall direct costs due to the surgical supply costs for each procedure (+$1830 for RALP) but also for the operating room costs (+$1187 for RALP; P < 0.001) reflecting the longer operative duration. Additional costs for purchase and maintenance (total of $340 000 per year when amortized over a 7-year period) of the robot would result in a cost of $2698 per patient undergoing RALP, given an average of 126 cases performed per year.
In our experience (Table 6), while RARP was clearly more expensive (+600 €) than open RP, the RASP was cheaper than OSP, principally due to the costs of hospitalisation. As previously shown in other recent series, the hospital stay is clearly longer for OSP, as patients are dismissed generally only after catheter removal. In addition, the need for several days of continuous catheter irrigation and the higher transfusion rate further increase the costs of hospitalisation in cases of OSP. TURis in our experience, had rather similar costs to RASP, fundamentally due to the hospitalisation (longer in patients with prostates of >100 mL) and to the cost of the resection loops.
Table 6. Costs: IEO experience
IO, intraoperative; PO, postoperative.
Cost in euros for:
Total cost, €
On the other hand, by sharply shortening the convalescence and the back-to-work time , the social impact (i.e. saving) of RA surgery might be more relevant, even if more difficult to quantify. However, some bias may have had an impact on the significance of these data: during the first 20 RASP procedures only three instruments were used, while at IEO, four or five instruments were used. Moreover operating room and hospitalisation costs were lower at SJH than in IEO, while surgical robotic disposable costs were higher at SJH due to a lower volume of RA procedures.
In conclusion, RASP is a feasible and reproducible procedure. For the patients, it presents the advantages of all minimally invasive approaches, i.e. short hospital stay, fast convalescence and return to work, and thus reducing the social cost of the disease. For the surgeon, it is easier to perform and to learn than pure laparoscopy. Consequently, the RA approach is worthy of consideration in cases of high-volume prostate adenomas.
As the incidence rate of high-volume obstructive prostate hyperplasia is rather low, the application of the RA approach for the SP needs good robotic skills (i.e. a concluded robotic learning curve) and the opportunity to ‘see the procedure’; for this purpose, information technology, e.g. Youtube™, presents a useful tool.