Surgical learning curve for robotic multiplex partial nephrectomy: The National Cancer Institute Experience.

Abstract

660 Background: Multiplex partial nephrectomy (MPN) remains the standard of care for hereditary and bilateral kidney tumors. Our institution is an international referral center for the management of hereditary renal cell carcinoma, and therefore has considerable experience with MPN. The objective of this study was to evaluate surgical learning curve for MPN among multiple surgeons at a single institution over an 11-year period. Methods: Retrospective review of a prospectively maintained registry of patients who underwent MPN from 2007-present. The first 100 consecutive surgeries of 3 NIH fellowship trained Urologic Oncologists were identified and evaluated in quartiles. Surgical outcome measures including operative duration (OD), estimated blood loss (EBL), number of tumors resected, and complication rate were chosen as surrogate markers of learning curve. Differences in individual surgeon outcomes were evaluated and variables including re-do surgery and surgical approach were considered. Significant differences found among quartiles or among surgeon were evaluated with multivariate logistic regression analysis. Results: A total of 300 MPN's were identified. In the quartile analysis, there were no significant differences in OD, EBL, numbers of tumors resected or rates of complication. Among surgeon factors, there were differences in surgical approach and EBL (table). In a multivariate analysis of factors associated with EBL, open approach (95%CI 245-831), p < 0.0001) and number of tumors (95%CI 43-82), p < 0.0001) were independently associated. No factors were associated increased rate of complication. Conclusions: As surgeons progressed through their first 100 operations, no true learning curve was appreciated, with similar outcomes in each quartile. Among surgeon factors, open surgical approach appears to drive difference in EBL.[Table: see text]