A systematic review and meta-analysis of oncological outcomes with transanal total mesorectal excision for rectal cancer.

AIM: Transanal total mesorectal (taTME) excision is a method used to assist in the radical removal of the rectum. By adopting the concept of natural orifice surgery, it offers potential benefits over conventional techniques. Early enthusiasm for this strategy led to its rapid and widespread adoption. The imposing of a local moratorium was precipitated by the discovery in Norway of an uncommon multifocal pattern of locoregional recurrence. The aim of this systematic review and meta-analysis was to determine the incidence of local recurrence after taTME for rectal cancer.

METHOD: Conforming to the Cochrane Handbook for Systematic Reviews of Interventions and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines checklist, a systematic review and meta-analysis was conducted. This included case series and comparative studies between taTME and preferentially laparoscopic procedures published between 2010 and 2021.

RESULTS: There were a total of 1175 studies retrieved. After removal and screening for quality and relevance, the final analysis contained 40 studies. The local recurrence rate following taTME was 3.4% (95% CI 2.9%-3.9%, I2  = 0%) in 4987 patients with follow-up durations ranging from 0.7 to 5.5 years. Compared with laparoscopic TME, local recurrence was not statistically different for the taTME group (p = 0.076); however, it was less probable (OR = 0.51, 95% CI 0.24-1.09, I2  = 0%). Systemic recurrence and circumferential resection margin status were secondary outcomes; however, the differences were not statistically significant.

CONCLUSION: Our data suggest that the local recurrence for regular laparoscopic and transanal TME surgeries may be comparable, suggesting that taTME can be performed without influencing locoregional oncological outcomes in patients treated at specialized institutions and who have been cautiously selected.