Published online Dec 27, 2022. doi: 10.4240/wjgs.v14.i12.1397
Peer-review started: October 2, 2022
First decision: October 30, 2022
Revised: November 6, 2022
Accepted: December 13, 2022
Article in press: December 13, 2022
Published online: December 27, 2022
Achieving a clear resection margins for low rectal cancer is technically challenging. Transanal TME (TaTME) has been introduced in order to address the chalenges associated with the open and laparoscopic TME (LaTME) in resecting low rectal tumours.
Previous meta-analyses have included mixed patients with mid and low rectal tumours when comparing TaTME and LaTME which has made the interpretation of the real differences between two approaches in treating low rectal cancer difficult.
To investigate the outcomes of transanal TaTME and LaTME in patients with low rectal cancer.
A comprehensive systematic review of comparative studies were conducted according to the standards of Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Intraoperative and postoperative complications, anastomotic leak, completeness of mesorectal excision, R0 resection, distal (DRM) and circumferential resection margin (CRM), number of harvested lymph nodes, and procedure time were the evaluated outcome parameters.
We identified twelve comparative studies enrolling a total of 969 patients comparing the outcomes of TaTME (n = 969) and LaTME (n = 476) in patients with low rectal cancer. The meta-analysis demonstrated that TaTME was associated with significantly lower rate of postoperative complications (OR: 0.74, P = 0.04), anastomotic leak (OR: 0.59, P = 0.02), and conversion to an open procedure (OR: 0.29, P = 0.002) compared with LaTME. Moreover, it was associated with significantly higher rate of R0 resection (OR: 1.96, P = 0.03). However, there was no significant difference in intraoperative complications (OR: 1.87; P = 0.23), completeness of mesoractal excision (OR: 1.57, P = 0.15), harvested lymph nodes (MD: -0.05, P = 0.96), DRM (MD: -0.94; P = 0.17), CRM (MD: 1.08, P = 0.17), positive CRM (OR: 0.64, P = 0.11) and procedure time (MD: -6.99 minutes, P = 0.45) between TaTME and LaTME.
Our findings indicated that for low rectal tumours, TaTME is associated with better clinical and short term oncological outcomes compared to LaTME.
The available evidence does not allow evaluation of long term oncological and functional outcomes. More randomized controlled trials are required to confirm the findings of this meta-analysis regarding clinical and short term oncological outcomes and to evaluate long term oncological and functional outcomes.