OBJECTIVETo compare the clinical efficacy of robotic and laparoscopic radical surgery in the treatment of middle-low rectal cancers.

METHODSFrom January 2015 to March 2016, intra-operative and postoperative follow-up data of 30 patients with middle-low rectal cancers who underwent robotic radical resection(robot group) and 32 patients with middle-low rectal cancers who underwent laparoscopic radical resection (laparoscopy group)n in our department were retrospectively collected. The distance from cancer to anal margin was less than 10 cm in both two groups and advanced rectal cancers were confirmed by preoperative colonoscopy biopsy. Associated data were compared between two groups.

RESULTSThere were 13 males and 17 females in robot group with age of 27 to 85 (mean 59.7) years, disease course of 3 to 12 (mean 6.2) months and clinical stage T2-3N0-1. There were 16 males and 16 females in laparoscopic group with age of 32 to 79 (mean 60.3) years, disease course of 2 to 10(mean 5.9) months and clinical stage T2-3N0-1. The baseline data of two groups were not significantly different (all P>0.05). All the patients in two groups completed operations successfully without conversion to open operation. Compared with laparoscopic group, the blood loss was less [(100.3±43.7) ml vs. (150.3±68.2) ml, t=3.413, P=0.001], the first flatus time [(49.3±12.4) h vs. (58.6±12.5) h, t=2.838, P=0.006] and urinary catheter removal time [(3.0±0.7) d vs. (4.8±0.9) d, t=5.491, P=0.000] were shorter, while the operation time [(217.3±57.8) min vs. (187.9±23.1) min, t=2.772, P=0.009] was longer in robot group. No cancer tissue was observed in resection margin of two groups. Number of harvested lymph node per case (15.2±7.4 vs. 13.9±4.9, t=-0.764, P=0.448), distance from anal margin to tumor distal edge [(7±3) cm vs. (6.5±3) cm, t=-1.952, P=0.056] and postoperative hospital stay [(13.6±1.3) d vs. (13.8±1.8) d, t=0.925, P=0.359] were not significantly different between two groups. No serious complications occurred in two groups during intra-operative and postoperative period. During following up of 3 to 12 (average 8.7) months, 1 case of anastomotic fistula occurred in each group and was cured by conservative treatment without significant difference [3.3%(1/30) vs. 3.1%(1/32), P=1.000]. No sexual dysfunction was found in either groups. Two cases in laparoscopic group presented relapse and metastasis, but no recurrence and metastasis was observed in robot group. There was no death in two groups.

CONCLUSIONRobotic radical surgery in the treatment of middle-low rectal cancers is safe and effective with the advantages of less trauma, less bleeding, rapid recovery of intestinal function and urinary function.