The surgical learning curve for laparoscopic radical prostatectomy: a retrospective cohort study

Abstract

Background We previously reported the learning curve for open radical prostatectomy, defined in terms of prostate cancer recurrence. We sought to characterize the learning curve for laparoscopic radical prostatectomy. Methods We conducted a retrospective cohort study of 5328 prostate cancer patients treated laparoscopically by one of 29 surgeons from 7 institutions in Europe and North America between 1998 and 2007. Multivariable models were used to evaluate the association between surgeon experience at the time of each patient's operation and prostate cancer recurrence, with adjustment for established predictors. Findings After adjusting for casemix, greater surgeon experience was associated with a lower risk of recurrence (P=0.0053). The 5-year risk of recurrence decreased from 17% to 16% to 9% for a patient treated by a surgeon with 10, 250 and 750 prior laparoscopic procedures (risk difference 8.0% 95% CI: 4.4%, 12.0%). The learning curve for laparoscopic radical prostatectomy was slower than the previously reported learning curve for open surgery (p<0.001). Surgeons with previous experience of open radical prostatectomy had significantly poorer results than those whose first operation was laparoscopic (risk difference 12.3%; 95% CI: 8.8%, 15.7%). Interpretation Increasing surgical experience is associated with substantial reductions in cancer recurrence after laparoscopic radical prostatectomy. Improvements in outcome seem to accrue more slowly in comparison with open surgery. Laparoscopic radical prostatectomy appears to involve skills that do not translate well from open experience. Funding source This paper was supported by funds from the National Cancer Institute, the Allbritton Fund and the David J. Koch Foundation.