BACKGROUND: Robotic lobectomy represents a paradigm shift for many surgeons. It is unknown if a surgeon's prior operative approach influences development of proficiency. We compared outcomes based on prior lobectomy experience and used cumulative sum (CUSUM) analysis to assess proficiency.

METHODS: Using the STS General Thoracic Database, we grouped surgeons as De novo, open- to-robotic or VATS-to-robotic. Operative time, blood transfusion, mortality and major morbidity were primary outcomes. Un/Acceptable thresholds were determined by review of the literature. Proficiency was defined as 20 consecutive cases without crossing an upper control line. Surgeons were assessed individually, and proficiency assessed by transition group.

RESULTS: From 2009-2016, 271 surgeons performed 5619 robotic lobectomies for clinical stage I/II non-small cell lung cancer. Of these, 65(24%) performed ≥20 lobectomies (4483 cases). Initial proficiency for an operative time target of 250 minutes was 40% for de novo compared to 14% of open-to-robotic and 21% of VATS-to-robotic surgeons, with improvement to 47%, 29% and 21% after 20 cases respectively. Initial and sustained proficiency related to major morbidity was similar for open-to-robotic and VATS-to-robotic, but lower for de novo at 40%. After 20 cases, most were proficient (de novo-93%, open-to-robotic-100% and VATS-to-robotic-86%). Proficiency for 30-day mortality and blood transfusion was high in all groups.

CONCLUSIONS: Outcomes among all transition groups improved with experience. OR duration proficiency was challenging for all groups. CUSUM may be useful to monitor proficiency in not only subsequent studies but in clinical practice.