Learning curve for laparoendoscopic single-site radical hysterectomy using the "chopstick" technique: a retrospective cohort study.

Background: Laparoendoscopic single-site surgery (LESS), as a promising minimally invasive surgery, is confronted with the obstacle of the "chopstick effect" which limits its further application. The "chopstick" technique is characterized by the usage of instruments of parallel and equal length, and in operations relying on double-fulcrum and unique surgeon position can play a key role in overcoming the above disadvantage effect. This study sought to explore the learning curve for the use of the novel "chopstick" technique in laparoendoscopic single-site radical hysterectomy (LESS-RH) and evaluate the technique's practicability. Methods: Consecutive cervical cancer patients who underwent LESS-RH with the "chopstick" technique by a surgeon with rich experience in laparoscopy from November 2016 to September 2018 were included in the study. The learning curve of his surgeries with the "chopstick" technique was evaluated using the cumulative summation (CUSUM) method by analyzing operation time (OT) which was the surrogate indicator of surgical ability. The patients were divided into Phase I and Phase II based on the learning curve peak, whose demographic and perioperative characteristics, such as tumor Federation International of Gynecology and Obstetrics (FIGO) stage and histology, operation time, blood loss, and complications were collected and analyzed. Results: The mean OT was 231.5 min (range, 115-355 min). The division of the learning curve based on OT occurred after the first 15 cases were finished, dividing Phase I and Phase II. The mean OT for Phase I (259 min) was significantly longer than that of Phase II (219 min) (P=0.02). Only 1 intraoperative complication occurred in Phase I, and none occurred in Phase II. Major postoperative complications occurred more frequently in Phase I (N=3) than in Phase II (N=0). No significant differences were observed in terms of lymph nodes, blood loss, or pathological features. Conclusions: The "chopstick" technique may help surgeons obtain stable LESS surgical performance through a relatively short learning curve, even in some complex surgeries, such as radical hysterectomy.