[Short-term efficacy of robotic-assisted total mesorectal excision with and without lateral lymph node dissection for mid-low advanced rectal cancer: a propensity score matching analysis].

Objective: To evaluate the feasibility, safety and efficacy of robotic-assisted lateral lymph node dissection for mid-low advanced rectal cancer. Methods: A retrospective cohort study was performed. Inclusion criteria: (1) age between 18 and 80 years old; (2) rectal adenocarcinoma diagnosed by pathology; (3) without distant metastasis by preoperative CT or MRI; (4) patients underwent robotic-assisted total mesorectal resection (TME). Exclusion criteria: (1) conversion to open surgery; (2) multiple primary tumors; (3) patients underwent combined multiple organ resection. According to the above criteria, 137 patients undergoing robotic-assisted mid-low rectal cancer resection in the First Affiliated Hospital of Xi'an Jiaotong University from December 2016 to April 2019 were enrolled. Ninety-seven cases underwent robotic-assisted total mesorectal excision (TME group) and 40 underwent robotic-assisted total mesorectal resection with lateral lymph node dissection (LLND) (TME+LLND group, pelvic LLND was performed with neurovascular guidance to retain pelvic autonomic nerves in the order of the left side the first and then the right side). The propensity score matching of 1:1 was performed with R software, based on age, sex, BMI, ASA classification, distance from tumor to the anal verge, preoperative chemoradiotherapy history, preoperative abdominal surgery history, the size of tumors and TNM stage. The operative indicators, postoperative recovery, pathology and postoperative complications within 30 days were compared between the two groups. Results: A total of 72 cases were successfully matched (36 in each group), and there were no statistically significant differences in baseline data between the two groups (all P>0.05). The operation time of TME+LLND group was significantly longer than that of TME group [275.0 (180-405) minutes vs. 220.0 (140-320) minutes, Z=-3.680, P<0.001], while there were no statistically significant differences in blood loss during operation, time to postoperative first flatus, postoperative hospital stay, total hospital cost, tumor differentiation, and distal resection length of margin (all P>0.05). Circumferential resection margin was all negative in both groups. The number of harvested lymph modes in the TME+LLND groups was higher than that in the TME group [26 (18-37) vs. 14 (9-36), Z=-6.407, P<0.001]. In addition, there were no statistically significant differences in postoperative morbidity and Clavien-Dindo classification of complication within 30 days between the two groups (both P>0.05). Conclusions: Although robotic lateral lymph node dissection requires longer operation time, it is a feasible, safe and effective procedure.目的： 探究机器人在直肠癌根治术中进行侧方淋巴结清扫（LLND）的可行性、安全性和有效性。 方法： 采用回顾性队列研究方法。病例纳入标准：（1）年龄18~80岁；（2）病理诊断确诊为直肠腺癌，肿瘤下缘距肛门距离≤8 cm；（3）术前CT、核磁等影像学检查评估未见远处转移；（4）接受机器人直肠癌全直肠系膜切除术（TME）。排除标准：（1）术中中转开腹；（2）存在同时性多原发肿瘤；（3）术中联合其他脏器切除。根据纳入排除标准，收集2016年12月至2019年4月间，在西安交通大学第一附属医院普通外科接受机器人直肠癌根治术的137例患者的临床资料。其中97例行达芬奇机器人TME（TME组）；40例行TME+LLND（TME+LLND组，采用神经-血管导向保留盆自主神经的盆腔LLND，按照先左侧后右侧的顺序进行）。根据患者性别、年龄、体质指数、美国麻醉医师分级、肿瘤距肛缘距离、术前放化疗史、术前腹部手术史、肿瘤长径及病理TNM分期等临床基本信息，用倾向性评分匹配对两组基线资料通过R语言软件、采用近邻法进行1∶1匹配，比较匹配后两组患者的手术情况、术后病理和恢复情况以及术后30 d内并发症发生情况。 结果： 共计72例（TME组和TME+LLND组各36例）配对成功，两组患者临床基线资料比较，差异均无统计学意义（均P>0.05）。TME+LLND组的手术时间明显长于TME组[275（180~405）min比220（140~320）min，Z=-3.680，P<0.001]，差异有统计学意义。两组患者在手术类型、术中出血量、术后首次通气时间、术后住院时间、住院总费用等方面比较，差异均无统计学意义（均P>0.05）。两组肿瘤分化程度以及肿瘤标本距远切缘距离的差异均无统计学意义（均P>0.05）。两组环周切缘均为阴性。TME+LLND组淋巴结清扫总数明显多于TME组[26（18~37）枚比14（9~36）枚，Z=-6.407，P<0.001]，差异有统计学意义。两组术后30 d内并发症发生总数及Clavien-Dindo各级并发症情况相比，差异均无统计学意义（均P>0.05）。 结论： 机器人直肠癌TME+LLND虽然会延长手术时间，但安全而有效。.