Robotic-assisted versus conventional laparoscopic surgery for endometrial cancer: long-term results of a randomized controlled trial

BACKGROUND: Robotic-assisted laparoscopy has become a widely and increasingly used modality of minimally invasive surgery in the treatment of endometrial cancer. Due to its technical advantages, robotic- assisted laparoscopic surgery offers benefits, such as a lower rate of conversions compared to conventional laparoscopy. Yet, data on longterm oncological outcomes after robotic-assisted laparoscopy is scarce and based on retrospective cohort studies only. OBJECTIVE: This study aimed to assess overall survival, progression-free survival, and long-term surgical complications in patients with endometrial cancer randomly assigned to robotic-assisted or conventional laparoscopy. STUDY DESIGN: This randomized controlled trial was conducted at the Department of Gynecology and Obstetrics of Tampere University Hospital, Finland. Between 2010 and 2013, 101 patients with low-grade endometrial cancer scheduled for minimally invasive surgery were randomized preoperatively 1:1 either to robotic-assisted or conventional laparoscopy. All patients underwent laparoscopic hysterectomy, bilateral salpingooophorectomy, and pelvic lymphadenectomy. A total of 97 patients (49 in the robotic-assisted laparoscopy group and 48 in the conventional laparoscopy group) were followed up for a minimum of 10 years. Survival was analyzed using Kaplan-Meier curves, log-rank test, and Cox proportional hazard models. Binary logistic regression analysis was used to analyze risk factors for trocar site hernia. RESULTS: In the multivariable regression analysis, overall survival was favorable in the robotic-assisted group (hazard ratio 0.39; 95% confidence interval [CI], 0.15-0.99, P=.047) compared to the conventional laparoscopy group. There was no difference in progression- free survival (log-rank test, P=.598). The 3-, 5-, and 10-year overall survival were 98.0% (95% CI, 94.0-100) vs 97.9% (93.8-100), 91.8% (84.2-99.4) vs 93.7% (86.8-100), and 75.5% (64.5-87.5) vs 85.4% (75.4-95.4) for the conventional laparoscopy and the robotic- assisted groups, respectively. Trocar site hernia developed more often for the robotic-assisted group compared to the conventional laparoscopy group 18.2% vs 4.1% (odds ratio 5.42, 95% CI, 1.11-26.59, P=.028). The incidence of lymphocele, lymphedema, or other long-term complications did not differ between the groups. CONCLUSION: The results of this randomized controlled trial suggest a minor overall survival benefit in endometrial cancer after robotic-assisted laparoscopy compared to conventional laparoscopy. Hence, the use of robotic-assisted technique in the treatment of endometrial cancer seems safe, though larger randomized controlled trials are needed to confirm any potential survival benefit. No alarming safety signals were detected in the robotic-assisted group since the rate of long-term complications differed only in the incidence of trocar site hernia.