A Meta-analysis Of Lateral Lymph Node Dissection In The Treatment Of Low Rectal Cancer After Preoperative Neoadjuvant Chemoradiotherapy

Purpose:Objective to systematically evaluate the clinical efficacy and safety of n CRT plus TME compared with n CRT plus TME plus LLND in the treatment of low rectal cancer.Method:A comprehensive search of the clinical randomized controlled trial or retrospective study comparing n CRT+TME+LLND and n CRT+TME was retrieved in Web of Science,Pub Med,Ovid Medline,Ovid Embase,Cochrane Library,Wan Fang database,VIP,CNKI and other Chinese and foreign databases,with the publication time from January 2000 to April 2021,and the required literature was finally screened after inclusion criteria and exclusion criteria set for the present study.The final included articles were examined by JADAD measuring scale or Newcastle-Ottawa Scale(NOS),and the outcome data of the included literatures were collected,and the Review Manager 5.3.would be use to analyze the extracted data.Result:8 articles were included,which were retrospective studies in English,including 2212 patients,(492 patients in the n CRT+TME+LLND group and 1720 patients in the n CRT+TME group).In terms of efficacy,there was no statistical difference in 5-year survival rate [HR = 0.97,95% CI(0.45,2.09),P = 0.93],5-year disease-free survival rate [HR = 0.97,95% CI(0.63,1.51),P = 0.91] between n CRT+TME+LLND group and n CRT+TME group.There were significant differences in local recurrence rate [OR= 0.44,95% Cl(0.26,0.76),P = 0.003],local pelvic lateral recurrence rate [OR = 0.25,95% Cl(0.10,0.65),P = 0.005],distant metastasis rate [OR = 0.57,95% Cl(0.36,0.90),P = 0.02].In terms of safety,the postoperative urinary dysfunction rate [OR = 2.44,95%CI(1.26,4.71),P = 0.008] was significantly increased in n CRT+TME+LLND group.In addition,the operation time of n CRT+TME+LLND group was significantly increased [WMD = 126.71,95% CI(77.21176.21),P < 0.00001].Conclusion:Although LLND would prolong the surgical duration and was related to increased postoperative urinary dysfunction which may be improved by the Da Vinci robotic surgery system or laparoscopic surgery.However,the results of this study support that the use of LLND after n CRT+TME can reduce the risk of local recurrence and distant metastasis for patients with clinically suspected LLNM,and provide another treatment option for patients suffer from low rectal cancer with high-risk.