Comparison Of Short-and Long-term Outcomes Between Laparoscope-assisted Transanal Total Mesorectal Excision And Laparoscopic Total Mesorectal Excision For The Treatment Of Mid And Low Rectal Cancer:A Meta-analysis

Objective: The aim of this study was to evaluate the therapeutic effects of transanal total mesorectal excision(Ta TME)and laparoscopic total mesorectal excision(La TME)in patients with rectal cancer.Methods: Pub Med,Embase,Cohrane Library,Chinese National Knowledge Infrastructure(CNKI),Chinese Biomedical Literature Database(CBM),Chinese Journal Full-text Database(VIP)and Wanfang Database were searched by electronic computer from database establishment to December 30,2020.The search language was limited to Chinese and English,and studies on transanal total mesorectal excision and laparoscopic total mesorectal excision for middle and low rectal cancer were included.Taking intraoperative blood loss,operation time,rate of conversion to laparotomy,incidence of intraoperative and postoperative complications,hospital stay,long-term survival rate and incidence of local recurrence or distant metastasis as the outcome measures of the study,the literatures were screened in strict accordance with the inclusion and exclusion criteria.Two independent studies extracted the data and evaluated the quality of the included literatures.When there were differences of opinions,the differences were first resolved through communication.If they could not be resolved,they were handed over to a third party for adjudication.The data were analyzed using Stata16.0 software.Results: A total of 24 articles were included in this meta-analysis,involving 3081 patients with low rectal cancer,1493 patients were treated with Ta TME and 1588 patients were treated with La TME.A total of 12 studies reported intraoperative blood loss in this meta-analysis.Meta-analysis results showed: [WMD =-36.66,95% CI(-74.37,1.05),P = 0.057],diamonds crossed the ineffective line,indicating that there was no significant difference in intraoperative blood loss between Ta TME and La TME in the treatment of patients with rectal cancer(P>0.05).Twenty studies reported the operation time.Meta-analysis showed: [WMD =-6.62,95% CI(-32.26,19.03),P = 0.613],diamonds crossed the ineffective line,indicating that after Ta TME and La TME were used to treat patients with rectal cancer,the difference in the operation time between the two surgical methods had no statistical significance(P >0.05).Twenty studies reported the length of hospital stay.Meta-analysis showed:[WMD =-1.02,95% CI(-2.14,0.10),P = 0.074],diamonds crossed the ineffective line,indicating that there was no significant difference in the length of hospital stay between the two surgical methods after Ta TME and La TME in the treatment of patients with rectal cancer(P>0.05).10 studies reported the incidence of intraoperative complications;Meta-analysis showed: [RR = 0.78,95% CI(0.62,0.98),P = 0.031],diamonds did not cross the ineffective line,indicating that after Ta TME and La TME for rectal cancer patients,the incidence of intraoperative complications of Ta TME was lower than La TME,and the difference had statistical significance(P <0.05).Eighteen studies reported the incidence of postoperative complications.Meta-analysis showed: [RR = 1.21,95% CI(1.08,1.37),P = 0.001],diamond did not cross the ineffective line,indicating that after Ta TME and La TME were used to treat patients with rectal cancer,the incidence of postoperative complications of Ta TME was higher than that of La TME,and the difference had statistical significance(P <0.05).Four studies reported the rate of conversion to laparotomy.Meta-analysis showed: [RD =-0.12,95% CI(-0.18,-0.06),P = 0.000],diamond did not cross the ineffective line,indicating that after Ta TME and La TME were used to treat patients with rectal cancer,the rate of conversion to laparotomy of Ta TME was lower than that of La TME,and the difference had statistical significance(P < 0.05).Nine studies reported the long-term survival rate.Meta-analysis showed: [RR = 1.01,95% CI(0.99,1.03),P = 0.374],the diamond crossed the ineffective line,indicating that there was no significant difference in the survival rate after the two surgical treatments after Ta TME and La TME for rectal cancer patients(P > 0.05).Six studies reported local recurrence and/or distant metastasis rate.Meta-analysis showed: [RR = 0.51,95% CI(0.51,1.73),P = 0.833],diamonds crossed the ineffective line,indicating that after Ta TME and La TME were used to treat patients with rectal cancer,there was no significant difference in local recurrence and/or distant metastasis rate after the two surgical treatments(P > 0.05).Conclusion: According to the existing literature evidence,it can be found that transanal total resection can reduce the incidence of intraoperative complications and the incidence of conversion to laparotomy to a certain extent,but the incidence of total postoperative complications is higher than the traditional laparoscopic total resection.There were no differences between the two surgical methods in terms of long-term survival,recurrence and tumor metastasis of patients.Therefore,in the treatment of middle and low rectal cancer,the therapeutic effects of the two surgical methods are similar.