Initial clinical experience with a novel flexible endoscopic robot for transanal surgery

Background: The Flex® Robotic System (Medrobotics, Raynham, MA, USA) is the first miniaturised flexible endoscopic robot that aims to allow surgical manoeuvres beyond the area currently reached by transanal endoscopic microsurgery. The aim of this study is to evaluate our initial clinical experience with this novel tool. Methods: We prospectively collected all consecutive cases of local excisions of rectal lesions performed with the Flex® Robotic System performed at the Department of Surgical Sciences of the University of Turin between October 2018 and December 2019. Indications were benign, or early rectal lesions judged unsuitable for endoscopic removal, within 20 cm of the anal verge. Debriefing meetings after each procedure allowed technology assessment leading to the modification, development, and implementation of tools according to the clinical experience. We analysed the data in terms of the safety and efficacy of treatment. Results: Between October 2018 and February 2020, 26 patients were treated. We performed a full-thickness excision in 14 patients and a submucosal dissection in 12. The median operating time was 115 min (range 45-360 min). In six patients (23.1%), we converted to standard transanal endoscopic operation (TEO®) (Karl Storz, Tuttlingen, Germany) to complete the procedure. The 30-day morbidity rate was 11.5% (3/26). Positive resection margins were detected in 4 (15.4%) patients. At a minimum follow-up of 12 months, 2 (7.7%) local recurrences were observed. Conclusions: This first clinical series demonstrates that the Flex® Robotic System is a fascinating technology that deserves further development to increase surgical dexterity, thereby overcoming current technical limitations and improving clinical outcomes.