Learning Curves of Ivor Lewis Totally Minimally Invasive Esophagectomy by Hospital and Surgeon Characteristics: A Retrospective Multinational Cohort Study.

OBJECTIVE: To describe the pooled learning curves of Ivor Lewis totally minimally invasive esophagectomy (TMIE) in hospitals stratified by predefined hospital- and surgeon-related factors. BACKGROUND: Ivor Lewis (TMIE is known to have a long learning curve which is associated with considerable learning associated morbidity. It is unknown whether hospital and surgeon characteristics are associated with more efficient learning. METHODS: A retrospective analysis of prospectively collected data of consecutive Ivor Lewis TMIE patients in 14 European hospitals was performed. Outcome parameters used as proxy for efficient learning were learning curve length, learning associated morbidity, and the plateau level regarding anastomotic leakage and textbook outcome. Pooled incidences were plotted for the factor-based subgroups using generalized additive models and 2-phase models. Casemix predicted outcomes were plotted and compared with observed outcomes. The investigated factors included annual volume, TMIE experience, clinic visits, courses and fellowships followed, and proctor supervision. RESULTS: This study included 2121 patients. The length of the learning curve was shorter for centers with an annual volume >50 compared to centers with an annual volume <50. Analysis with an annual volume cut-off of 30 cases showed similar but less pronounced results. No outcomes suggesting more efficient learning were found for longer experience as consultant, visiting an expert clinic, completing a minimally invasive esophagectomy fellowship or implementation under proctor supervision. CONCLUSIONS: More efficient learning was observed in centers with higher annual volume. Visiting an expert clinic, completing a fellowship, or implementation under a proctor's supervision were not associated with more efficient learning.