ENDOUROLOGY & LAPAROSCOPY

doi: 10.1590/S1677-55382010000600018

The learning curve for laparoscopic radical prostatectomy: an international multicenter study
Secin FP, Savage C, Abbou C, de La Taille A, Salomon L, Rassweiler J, Hruza M, Rozet F, Cathelineau X, Janetschek G, Nassar F, Turk I, Vanni AJ, Gill IS, Koenig P, Kaouk JH, Martinez Pineiro L, Pansadoro V, Emiliozzi P, Bjartell A, Jiborn T, Eden C, Richards AJ, Van Velthoven R, Stolzenburg JU, Rabenalt R, Su LM, Pavlovich CP, Levinson AW, Touijer KA, Vickers A, Guillonneau B
Department of Urology, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
J Urol. 2010; 184: 2291-6

• Purpose: It is not yet possible to estimate the number of cases required for a beginner to become expert in laparoscopic radical prostatectomy. We estimated the learning curve of laparoscopic radical prostatectomy for positive surgical margins compared to a published learning curve for open radical prostatectomy.
  Materials and Methods: We reviewed records from 8,544 consecutive patients with prostate cancer treated laparoscopically by 51 surgeons at 14 academic institutions in Europe and the United States. The probability of a positive surgical margin was calculated as a function of surgeon experience with adjustment for pathological stage, Gleason score and prostate specific antigen. A second model incorporated prior experience with open radical prostatectomy and surgeon generation.
  Results: Positive surgical margins occurred in 1,862 patients (22%). There was an apparent improvement in surgical margin rates up to a plateau at 200 to 250 surgeries. Changes in margin rates once this plateau was reached were relatively minimal relative to the CIs. The absolute risk difference for 10 vs 250 prior surgeries was 4.8% (95% CI 1.5, 8.5). Neither surgeon generation nor prior open radical prostatectomy experience was statistically significant when added to the model. The rate of decrease in positive surgical margins was more rapid in the open vs laparoscopic learning curve.
  Conclusions: The learning curve for surgical margins after laparoscopic radical prostatectomy plateaus at approximately 200 to 250 cases. Prior open experience and surgeon generation do not improve the margin rate, suggesting that the rate is primarily a function of specifically laparoscopic training and experience.

• Editorial Comment
  This multi-institutional study redefined some of the end points to measure improvement of learning curve for laparoscopic radical prostatectomy (LRP).
  The authors reported previously biochemical recurrence as measurement of surgical technique improvement. The currrent study focused on positive surgical margins (PSM) rates to determine the effects of changes in technique or training. This study estimated the overall PSM rate among patients treated with LRP without robotic assistance at North American and European institutions, and estimated the learning curve using PSMs as an end point. In addition, it was evaluated the effects of prior open experience and whether first generation surgeons had results different from those of the second generation who benefitted from experience. The authors compared the laparoscopic radical prostatectomy (RP) learning curve for PSMs to that of open RP, and examined the margins learning curve in light of the learning curve for biochemical recurrence.
  PSMs were reported in 1,862 patients (22%) of this multicenter series. The learning curve for PSMs after LRP, although fairly similar to that of the open technique, appears to be slower. SM rates improve with increasing surgeon experience until a plateau at around 200 to 250 cases. Prior open experience and surgeon generation do not improve margin rates, suggesting that these are primarily a function of specifically laparoscopic experience.

Dr. Fernando J. Kim
Chief of Urology, Denver Health Med. Ctr.
Associate Professor, Univ. Colorado Health Sci. Ctr.
Director of Minimally Invasive Urol. Oncology, UCHSC
Denver, Colorado, USA
E-mail: fernando.kim@dhha.org