[Efficacy comparison of robotic and laparoscopic radical resection of rectal cancer for overweight and obese patients].

Objective: During laparoscopic pelvic operational procedure for obese patients with rectal cancer, the large amount of fat in the abdominal cavity often impairs the exposure of the surgical field, resulting in technical difficulty. In contrast, robotic surgery has the advantages of being more minimally invasive, precise, and flexible. This study compared the clinical efficacy of robotic and laparoscopic radical resection of rectal cancer for overweight and obese patients. Methods: A retrospective cohort study was conducted. Clinical data of 173 patients with rectal cancer and a body mass index (BMI) ≥ 25 kg/m(2) who received robotic or laparoscopic radical rectal resection at the First Affiliated Hospital of Nanchang University from January 2015 to February 2019 were retrospectively collected. Of 173 patients, 90 underwent robotic surgery and 83 underwent laparoscopic surgery. The intraoperative parameters, postoperative short-term and follow-up status were analyzed and compared between the two groups. The follow-up ended in December 2019. Results: Of 173 patients, 103 were male and 70 were female with a median age of 62 (range 29 to 86) years. The average BMI was (27.2±1.6) kg/m(2) in the robotic group and (27.3±1.5) kg/m(2) in the laparoscopic group. No significant differences in baseline data were observed between two groups (all P >0.05). As compared to the laparoscopic group, the robotic group had less intraoperative blood loss [(73.0±46.8) ml vs. (120.9±59.9) ml, t =-5.881, P <0.001] and higher postoperative hospitalization expense [(61±15) thousand yuan vs (52±13) thousand yuan, t =3.468, P =0.026]. The conversion rate in the robotic group was 1.1% (1/90), which was lower than 6.0% (5/83) in the laparoscopic group, but the difference was not statistically significant ( P =0.106). There were no statistically significant differences between the two groups in operative time, number of intraoperative blood transfusion, number of harvested lymph nodes, time to the first flatus, postoperative hospital stay and morbidity of total postoperative complications (all P >0.05). Five (6.0%) patients in the laparoscopic group developed urinary dysfunction, while no case in the robotic group developed postoperative urinary dysfunction ( P =0.024). The 173 patients were followed up for 8-59 months, with a median follow-up of 36 months. The 3-year overall survival rate of robotic group and laparoscopic group was 89.8% and 86.6%, respectively without significant difference between the two groups ( P =0.638). The 3-year disease-free survival rate of the robotic group and the laparoscopic group was 85.6% and 81.5%, respectively without significant difference as well ( P =0.638). Conclusions: Robotic radical surgery is safe and feasible for overweight and obese patients with rectal cancer. Compared with laparoscopic radical surgery, it has advantages of clear vision of surgical exposure, less intraoperative blood loss, less pelvic autonomic nerve damage, and operation in a narrow space.