Clinical and oncological outcomes of transanal total mesorectal excision considering the embryology along the fascia in rectal cancer patients: a propensity score-matched analysis

Purpose: Transanal total mesorectal excision (TaTME) remains a challenging technique for rectal dissection. This study aims to evaluate the clinical and oncological outcomes of TaTME, compared to those of the laparoscopic total mesorectal excision (LaTME) in rectal cancer. Methods Using propensity score-matched analyses, we analyzed retrospective data from 134 consecutive patients with rectal cancer who underwent TaTME or LaTME from January 2011 to June 2020 in our hospital. Clinical and oncological outcomes were evaluated. The primary endpoint was the 2-year local recurrence rate. Results Before data analysis, significant group-dependent differences were observed only in the tumor height (p < 0.01). After analysis, preoperative patients’ demographics were similar between the TaTME and LaTME-defined groups. The operative time was significantly shorter in the TaTME group (p = 0.02), and the rates of hand-sewn anastomosis and protective loop ileostomy were significantly higher(p < 0.01). TaTME showed a 29% overall morbidity rate and LaTME 44%. Furthermore, the rate of Clavien–Dindo grade III tended to be lower in the TaTME group (p = 0.07). There were no statistically significant differences in terms of pathological findings, and the 2-year local recurrence rate was similar between the two groups (both 5.9%) Conclusions TaTME based on embryology along the fascia is feasible and seems a safe alternative to LaTME in selected patients with rectal cancer when considering the conversion rate and the operative time.