A nationwide comparison of short-term outcomes after transanal, open, laparoscopic, and robot-assisted total mesorectal excision

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.