The outcomes of robotic radical prostatectomy are highly dependent on the surgeon's technique and most important, experience. Sexual and urinary function outcomes, as well as cancer-specific results (particularly positive surgical margins) have a strong association with the case volume.
1) How many robotic prostatectomy cases has the surgeon performed?
The learning curve for robotic prostatectomy has been well studied over the recent years. Debate on the definition of "learning curve" remains controversial.
- Learning curves related to proficiency on the da Vinci robot have been reported to be significantly shorter than that for the straight laparoscopic approach.1
- It has been estimated to include 15–30 cases to become familiar with the device and procedure.2,3
- Operative skin-to-skin times <4 hours often require 25-150 cases to be performed.4,5
- With regards to program development, particularly for robotic-naïve surgeons with either laparoscopic or retropubic prostatectomy training, key components to implement a successful robotics program include a dedicated nursing team and bed-side assistants.
1. Menon M, Shrivastava A, Tewari A, Sarle R, Hemal A, Peabody JO, Vallancien G. Laparoscopic and robot assisted radical prostatectomy: establishment of a structured program and preliminary analysis of outcomes. J Urol 2002; 168:945-949.
2. Patel VR, Tully AS, Holmes R, Lindsay J. Robotic radical prostatectomy in the community setting--the learning curve and beyond: initial 200 cases. J Urol 2005;174:269-272.
3. Ahlering TE, Skarecky D, Lee D, Clayman RV. Successful transfer of open surgical skills to a laparoscopic environment using a robotic interface: initial experience with laparoscopic radical prostatectomy. J Urol 2003;170:1738-1741.
4. El-Hakim A, Leung RA, Tewari A. Robotic prostatectomy: a pooled analysis of published literature. Expert Rev Anticancer Ther 2006;6:11-20.
5. Zorn KC, Orvieto MA, Gong EM, Mikhail AA, Gofrit ON, Zagaja GP, Shalhav AL. Robotic radical prostatectomy learning curve of a fellowship-trained laparoscopic surgeon. J Endourol 2007; 21:441-447.
2) How many cases are done on a weekly/monthly basis?
- Higher provider volumes (>50 cases/year) are associated with better outcomes, both sexual and cancer-control, after radical prostatectomy. 8,9,10,11,12
- Ideally, centers of excellence will have high robotic prostatectomy volume (10-20 procedures/week). Although no randomized studies have evaluated the impact of case number per week and surgical outcomes, the greater the surgeon’s experience, the better the surgical outcomes— specifically blood loss, operative time and positive margin rate. Robotic teams with the greatest experience (as described in the figure above) often have the highest surgical density.
8. Wilt TJ, Shamliyan TA, Taylor BC, Macdonald R, Kane RL. Association Between Hospital and Surgeon Radical Prostatectomy Volume and Patient Outcomes: A Systematic Review. J Urol 2008; in press.
9. Joudi FN, Konety BR. The volume/outcome relationship in urologic cancer surgery. Support Cancer Ther 2004; 2:42-46
10. Denberg TD, Flanigan RC, Kim FJ, Hoffman RM, Steiner JF. Self-reported volume of radical prostatectomies among urologists in the USA. BJU Int 2007; 99:339-343.
11. Chun FK, Briganti A, Antebi E, Graefen M et al. Surgical volume is related to the rate of positive surgical margins at radical prostatectomy in European patients. BJU Int 2006; 98:1204-1209.
12. Klein EA, Bianco FJ, Serio AM, Eastham JA, Kattan MW, Pontes JE, Vickers AJ, Scardino PT. Surgeon experience is strongly associated with biochemical recurrence after radical prostatectomy for all preoperative risk categories. J Urol 2008; 179:2212-2216.
3) What is the average operative time?
As a surgeon gains familiarity with the robotic technique, the surgical time will significantly decrease.
4) What is your positive margin rate?
A positive surgical margin (PSM) is a pathological diagnosis after prostate removal. The gland is routinely stained with a blue dye and thinly sectioned like a loaf of bread. Under the microscope, the pathologist evaluates the outer edges of the specimen. If cancer cells are present along the inked-boarders, a PSM is noted.
Figure: High power (40x-magnification) of pT2 positive surgical margin. Note the capsular violation (black arrow) exposing prostatic adenocarcioma at the inked margins (white arrow).
A PSM means that cancer cells may have been left in the pelvis and may be a source for disease recurrence. The risk of cancer recurrence is largely related to the margin status. In the best of experienced surgeons’ hands, the overall PSM rate is low (<10-20%).
Table 1. Positive surgical margin rates and biochemical recurrence rates reported in large open, laparoscopic and robot-assisted laparoscopic radical prostatectomy series.
5) Have your results ever been published?
Only published data should be used to counsel patients during treatment planning. Peer-review is a process of subjecting an author's scholarly work, research or ideas to the scrutiny of others who are experts in the same field. It is used primarily by editors to select and to screen submitted manuscripts, and by funding agencies, to decide the awarding of grants. The peer review process aims to make authors meet the standards of their discipline and of science in general. Publications and awards that have not undergone peer review are likely to be regarded with suspicion by scholars and professionals in many fields.