Surgical learning curve for open radical prostatectomy: Is there an end to the learning curve?

OBJECTIVES: To analyze the impact of surgeon's experience on surgical margin status, postoperative continence and operative time after radical prostatectomy (RP) in a surgeon who performed more than 2000 open RP. PATIENTS AND METHODS: We retrospectively analyzed 2269 patients who underwent RP by one surgeon from April 2004 to June 2012. Multivariable logistic models were used to quantify the impact of surgeon's experience (measured by the number of prior performed RP) on surgical margin status, postoperative continence and operative time.
RESULTS: Negative surgical margin rate was 86 % for patients with pT2 stage, and continence rate at 3 years after RP was 94 %. Patients with negative surgical margin had lower preoperative PSA level (p = 0.02), lower pT stage (p < 0.001) and lower Gleason score (p < 0.001). The influence of the experience of the surgeon was nonlinear, positive and highly significant up to 750 performed surgeries (75-90 % negative surgical margin) (p < 0.01). The probability of continence rises significantly with surgeon's experience (from 88-96 %) (p < 0.05). A reduction in operative time (90-65 min) per RP was observed up to 1000 RP.
CONCLUSIONS: In the present study, we showed evidence that surgeon's experience has a strong positive impact on pathologic and functional outcomes as well as on operative time. While significant learning effects concerning positive surgical margin rate and preserved long-term continence were detectable during the first 750 and 300 procedures, respectively, improvement in operative time was detectable up to a threshold of almost 1000 RP and hence is relevant even for very high-volume surgeons.