Comparison of transanal total mesorectal excision and robotic total mesorectal excision for low rectal cancer after neoadjuvant chemoradiotherapy

Background To improve the quality of surgery for rectal cancer, both transanal total mesorectal excision (taTME) and robotic total mesorectal excision (R-TME) can be performed. However, few studies have compared outcomes of taTME and R-TME, especially for patients with low rectal cancer after undergoing neoadjuvant chemoradiation (nCRT). Thus, the objective of this study was to compare outcomes of taTME and R-TME for patients with low rectal cancer after undergoing nCRT. Methods A total of 306 consecutive patients with low rectal cancer who underwent taTME or R-TME after nCRT between 2008 and 2018 were analyzed retrospectively. Patients were classified into two groups: 1) taTME surgery group (n = 94); and 2) R-TME surgery group (n = 212). Results Clinicopathologic variables were comparable between the two groups. There was no significant difference in circumference margin involvement (1.1% in taTME vs. 2.8% in R-TME, p = 0.680) or distal resection margin (2.3 cm in taTME vs. 2.4 cm in R-TME, p = 0.629). Total operation time (239 min in taTME vs. 243 min in R-TME, p = 0.675) and major complications (including anastomosis site leakage, surgical site infection, and voiding difficulty) showed no significant difference between the two groups either. Conclusions Transanal and robotic TMEs have similar short-term outcomes for patients with rectal cancer after undergoing nCRT. High quality TME can be equally achieved with both transanal and robotic approaches.