The influence of learning curve of robot-assisted laparoscopy on oncological outcomes in early stage cervical cancer: an observational cohort study

Abstract

Objective: To investigate the learning curve of robot-assisted laparoscopy in early stage cervical cancer and quantify impact on oncological outcomes. Design: Observational cohort study. Setting: Tertiary referral centre with one surgical team. Population: All early stage cervical cancer patients treated consecutively with robot-assisted laparoscopy between 2007 and 2017. Methods: With multivariate risk-adjusted cumulative sum analysis (RA-CUSUM), we assessed the learning curve of robot-assisted laparoscopy of a single surgical team based on cervical cancer recurrence. Subsequently, a survival analysis was conducted comparing oncological outcomes of patients treated during different phases of the learning curve. Main Outcome Measures: Surgical proficiency based on recurrence, survival rates in the different learning phases. Results: 165 cervical cancers patients were operated by robot-assisted laparoscopy, with a median follow-up of 57 months (range 3-132 months). The RA-CUSUM analysis demonstrated two phases of the learning curve: a learning phase of 61 procedures (group 1) and an experienced phase representing the 104 procedures thereafter (group 2). The 5-year disease free survival was 80.2% in group 1 and 91.1% in group 2 (P = 0.040). Both the 5-year disease-specific survival and overall survival significantly increased after the learning phase. Conclusion: The learning phase of robot-assisted laparoscopy in early stage cervical cancer in this institutional cohort is at least 61 procedures, with higher survival rates in the patients treated thereafter. The learning curve of robot-assisted laparoscopy affects oncological outcomes and warrants more attention in the design of future studies. Funding: None. Keywords: Cervical cancer, robot-assisted laparoscopy, learning curve, RA-CUSUM, recurrence, survival.