Robotic vs. TaTME Rectal Surgery (ROTA STUDY)

Background Recent novel surgical techniques for resection of low rectal cancer have been introduced and these approaches have the potential to overcome anatomical limitations like obesity, narrow male pelvis and bulky and low tumours. Two of these procedures are robotic low anterior resection (RLAR) and transanal total mesorectal excision (TaTME). Both approaches have distinct advantages and limitations however there have been no head to head trial comparing RLAR and TaTME for patients with mid to low rectal cancer undergoing surgery by experienced surgeons. Previous studies looking at the oncological outcomes of either TaTME or robotic TME included many centres where the surgeons were on a learning curve and hence the true oncological outcomes and clinical benefits cannot be measured accurately. The primary objective of this pilot study is to conduct a multicentre prospective trial to investigate clinical outcomes, in particular disease free survival (DFS) in patients undergoing RLAR and TaTME. The additional goal is to investigate other efficacy measures, complications rates, recruitment feasibility and protocol refinement. Method This pilot study will be a prospective, observational, case-matched, two -cohort, multicentre designed to investigate the oncological and clinical outcomes of patients with mid-to-low, non-metastatic rectal cancer undergoing low anterior resection (LAR) using robot-assisted surgery ( RLAR), or transanal total mesorectal excision (TaTME). The inclusion criteria consist of experienced surgeons defined as 60 prior procedures with RLAR or TaTME to meet the enrolment criteria for the RLAR and TaTME arm, respectively. Successful oncological and clinical outcomes are defined as circumferential resection margin (CRM) ≥1 mm with minimal postoperative morbidity (absence of Clavien-Dindo grade III-IV complications within 30 days after surgery). Local and distal recurrence rates with DFS over 3 years will be measured as primary outcome. Secondary and exploratory endpoints will include length of hospital stay, intraoperative time, intraoperative blood loss, harvested lymph nodes, distal resection margin, incompleteness of mesorectum, CRM involvement, unplanned conversion rates, 30-days postoperative complications and overall recurrence rate. The Quality of life assessment questionnaires will be performed preoperatively, 6 months and 12 months after reversal of ileostomy. Propensity score matching will be used to minimize bias from the nonrandomized treatment assignment. The RLAR and TaTME cohorts will be matched by propensity scores accounting for factors significantly associated with either undergoing robotic surgery or TaTME occurrence on logistic regression analysis. Ethics and Dissemination The medical ethical committees of all the participating countries will be involved in approving the study protocol. Results of the primary and secondary end points will be submitted for publication in peer-reviewed journals.