AIM: Laparoscopic rectal cancer surgery has several limitations. Transanal total mesorectal excision (TaTME) can potentially overcome these limitations. The aim of this study was to compare the rates of non-radical surgery and anastomotic leakage after TaTME, open TME (OpTME), laparoscopic TME (LaTME) and robotic TME (RoTME) procedures in a nationwide cohort.

METHODS: We extracted the demographic, perioperative and pathological data of patients who underwent a curative OpTME, LaTME, RoTME or TaTME procedure between January 2014 and December 2018 from the national database of the Danish Colorectal Cancer Group (DCCG). We conducted multiple group-comparisons, uni- and multivariate analyses to determine the factors associated with positive resection margin (+RM) and anastomotic leakage.

RESULTS: We included 2393 patients (OpTME = 205, LaTME = 1163, RoTME = 713 and TaTME = 312). The rate of +RM was 5.7% after TaTME. The lowest rate of +RM was achieved after RoTME (8.2%, 4.7%, 2.52%, and 5.7%, after OpTME, LaTME, RoTME and TaTME respectively, p < 0.001). In multivariate analysis, having a T4 tumour and intraoperative bowel perforation were associated with the risk of +RM (p < 0.001, p < 0.001, respectively). The factors associated with anastomotic leakage in multivariate analysis were male gender, high BMI and intraoperative bowel perforation (p < 0.001, p = 0.049, p = 0.002, respectively). TaTME was associated with the highest rate of sphincter-saving procedures (79.8%, p < 0.001), the lowest rate of bowel perforation (2.9%, p = 0.028) and the lowest rate of conversion to open surgery (1.3%, p < 0.001).

CONCLUSIONS: In a nationwide audit of TME approaches, the rate of +RM was lowest after RoTME. No differences were found between the four approaches regarding the risk of anastomotic leakage. TaTME offered advantages related to sphincter-saving, perforation and conversion.