DaVinci-assisted laparoscopic radical prostatectomy: the learning curve

Objective: To define the learning curve for daVinci-assisted laparoscopic radical prostatectomy (DLP) at our institution. Methods: The data from 170 patients who underwent DLP between August 2002 and December 2004 by a single surgeon (MTG) were reviewed. Operative time, hemoglobin decrease, conversion to open procedure, positive margin rates, complications, length of stay (LOS), length of catheterization, continence, and erectile function were analyzed. Results: Hemoglobin decrease (p=0.11), positive margin rates (p=0.80), and early urinary continence (p=0.17) did not significantly correlate with surgical experience. A trend towards lower complications (p=0.07) and an earlier return of erectile function (p=0.09) was noted with increased experience with DLP. Operative time, hospital stay, catheterization time, and open conversion showed significant association with patient sequence. Median operative time for the first 60 and the last 110 patients was 323.5 and 239.5 minutes (p=< 0.0001), respectively. Median LOS for the aforementioned groups was 53 and 51 hours (p=0.009). Length of catheterization declined significantly between the first 60 and the remaining 110 patients, 14 as compared to 11.5 days (p=< 0.0001). Eight open conversions occurred, six were in the first 30 patients (p=0.03). Conclusion: As an indicator of the learning curve, the operative time in our series showed no correlation with sequence after the 60(th) patient. Thus, despite the advantages of robotics, the learning curve to efficient performance of daVinci-assisted laparoscopic radical prostatectomy is long. Oncological and functional outcomes should not be affected during the learning curve.