The role of transanal total mesorectal excision in the treatment of rectal cancer: a systematic review

INTRODUCTION: Total mesorectal excision (TME) during rectal resection is considered the gold standard for the treat- ment of rectal cancer. Transanal total mesorectal excision (TaTME) was first described in 2010 and has been applied to humans since 2012 to overcome some of the technical difficulties associated with minimally invasive TMEs. EVIDENCE ACQUSITION: A systematic review of the literature was conducted, and it focused on articles published between 2012 and 2022 to analyze the state of the art of surgical techniques and indications, as well as potential technical, oncological, and functional benefits. EVIDENCE SYNTHESIS: The indications for TaTME are not yet standardized, and structured training programs are necessary to complete a safe learning curve for this new technique. The procedure, when compared with conventional open or minimally invasive TME, is feasible and safe with similar intraoperative and postoperative complications. On the other hand, some new specific complications of this new approach have been described. The short-term pathological and oncologic results are encouraging, especially in terms of the mesorectal specimen quality, distal resection margin and conversion rate. Also, the functional results seem encouraging when compared with other minimally invasive techniques. CONCLUSIONS: Long-term follow-up and ongoing RCT trials are fundamental to evaluate the possible benefits in terms of local recurrence and survival. This will facilitate the comparison with other minimally invasive rectal resections.