Laparoscopic total mesorectal excision versus transanal total mesorectal excision for mid and low rectal cancer: A systematic review and meta-analysis

Background: Laparoscopic total mesorectal excision (LaTME) and transanal total mesorectal excision (TaTME) are popular mid and low rectal cancer trends. However, there is currently no systematic comparison between LaTME and TaTME of mid and low rectal cancer. Therefore, we systematically study the perioperative and pathological outcomes of LaTME and TaTME in mid and low rectal cancer. Methods: Articles included searching through the Embase, Cochrane Library, PubMed, Medline, and Web of science for articles on LaTME and TaTME. We calculated pooled standard mean difference (SMD), relative risk (RR), and 95% confidence intervals (CIs). The protocol for this review has been registered on PROSPERO (CRD42022380067). Results: There are 8761 participants included in 33 articles. Compared with TaTME, patients who underwent LaTME had no statistical difference in operation time (OP), estimated blood loss (EBL), postoperative hospital stay, over complications, intraoperative complications, postoperative complications, anastomotic stenosis, wound infection, circumferential resection margin, distal resection margin, major low anterior resection syndrom, lymph node yield, loop ileostomy, and diverting ileostomy. There are similarities between LaTME and TaTME for 2-year DFS rate, 2-year OS rate, distant metastasis rat, and local recurrence rate. However, patients who underwent LaTME had less anastomotic leak rates (RR 0.82; 95% CI: 0.70-0.97; I2 = 10.6%, P = .019) but TaTME had less end colostomy (RR 1.96; 95% CI: 1.19-3.23; I2 = 0%, P = .008). Conclusion: This study comprehensively and systematically evaluated the differences in safety and effectiveness between LaTME and TaTME in the treatment of mid and low rectal cancer through meta-analysis. Patients who underwent LaTME had less anastomotic leak rate but TaTME had less end colostomy. There is no difference in other aspects. Of course, in the future, more scientific and rigorous conclusions need to be drawn from multi-center RCT research.