Introduction: We aimed to document the learning curve for the laparoscopic radical prostatectomy (LRP) procedure and determine the most reliable outcomes for reporting surgeon performance.

Materials and Methods: Using prospectively collected data from the first series of patients to undergo LRP by two different surgeons in the same institution, linear and logistic regression analyses were carried out to graphically represent the surgical learning curve for operative time, blood loss, complications, length of stay (LOS) and positive margins. Surgeon A carried out 275 operations between 2003-2009; Surgeon B carried out 225 between 2008-2012. Comparison by groups of 25 consecutive patients was carried out with multivariate analysis and estimation of predicted probabilities.

Results: Learning curves showing continuous improvement of operative time, blood loss, complications, LOS and T2 positive margins were demonstrated for both cohorts. For surgeon A, a plateau was observed for length of stay and T2 positive margins after 100 and 150 surgeries respectively. No such plateau was observed for surgeon B. The predicted probability of a T2 positive margin decreased from >25% at the start of surgeon B’s cohort to <10% after 75 operations, whilst for surgeon A, predicted probability decreased from around 50% at 100 cases to <10% after 250 cases.

Conclusion: Here we showed that the most informative outcome measure, with the least potential observer bias, was T2 positive margins. In the era of individual surgeon reported outcomes, this highlights the potential for use of a single objective outcome measure representative of improvement in surgeon skill over time.