Improvements in Robot-Assisted Prostatectomy

Improvements in Robot-Assisted Prostatectomy: The Effect of Surgeon Experience and Technical Changes on Oncologic and Functional Outcomes.

David B. Samadi, M.D.,1 Paul Muntner, Ph.D., Fatima Nabizada-Pace, M.P.H., Jonathan S. Brajtbord, B.S., John Carlucci, M.D., and Hugh J. Lavery, M.D.

Abstract

Purpose: To assess the effect of surgeon experience and technical modifications on functional and oncologic outcomes after robot-assisted laparoscopic prostatectomy (RALP).

Patients and Methods:

Data were available for 1181 of 1420 consecutive patients undergoing RALP by a single surgeon (DBS). Three techniques were evaluated. The ‘‘initial’’ technique included incision of the lateral endopelvic fascia, suture ligation of the dorsal venous complex (DVC), and anterior tennis-racquet bladder neck reconstruction (n¼590 procedures). The ‘‘intermediate’’ technique included a modified ‘‘curtain’’ nerve-sparing technique and incision of the DVC without previous ligation (n?170). The ‘‘current’’ technique uses a posterior tennis-racquet bladder neck reconstruction (n?421). Outcomes included continence and potency recovery and the presence of pT2 surgical margins assessed in continuous fashion. Validated questionnaires were used to assess baseline and postoperative functional outcomes.

Results: Continence rates improved between techniques at all evaluated time points, with 1-year continence rates of 88%, 93%, and 96% in the initial, intermediate, and current technique groups, respectively (Ptrend <0.001). One-year potency rates, however, remained similar among the groups, with rates of 77%, 84%, and 79%, respectively (P?0.58). pT2 margin rates decreased continuously during the initial technique period, followed by a transient worsening of margin rates during the intermediate time period and a subsequent decrease during the period when the current technique was used.

Conclusions: Increased experience with robot-assisted prostatectomy resulted in improvements in oncologic and functional outcomes. Modifications to robot-assisted prostatectomy techniques may aid in this improvement but are also associated with transient worsening of outcomes during the learning curve of the new technique.

Introduction

The intuitive concept that surgeons improve with experience has been repeatedly demonstrated in regard to outcomes after open1,2 and laparoscopic radical prostatectomy. 3 A recent study demonstrated continuous improvement, without a plateau even at 1000 cases, for laparoscopic radical prostatectomy.3 One hypothesis for this finding was that the improvements in outcomes over time were a function of ‘‘profession-wide modifications’’ to a recently developed technique, rather than the technical improvements of laparoscopic surgeons. Profession-wide modifications are occurring in robot-assisted laparoscopic prostatectomy (RALP) fairly frequently, yet their impact on outcomes is poorly understood. To assess whether changes in outcomes are a function of surgeon experience vs technique modifications, we evaluated the change in oncologic and functional outcomes after RALP in two ways: As a function of the number of procedures performed and as a function of ‘‘procedural eras.’’

A steady, continuous improvement in outcomes over the number of procedures performed would suggest that a prolonged learning curve of technical refinement occurs. In contrast, improvements in outcomes followed by a plateau after major procedural modifications would suggest that a change in technique is responsible for the improvements. A third alternative is that some technical modifications are associated with a new learning curve and that outcomes are transiently worse before improvements become apparent. We evaluated this hypothesis in the setting of more than 1100 procedures conducted by a single, high-volume robotic surgeon. Using a single surgeon and a standardized technique minimizes the variability of surgeon-dependent variables. With previous training in both pure laparoscopic and open radical prostatectomy, this surgeon’s robotic learning curve should not have been affected by a need to relearn the surgical anatomy from a laparoscopic perspective.