Total mesorectal excision in MRI-defined low rectal cancer: multicentre study comparing oncological outcomes of robotic, laparoscopic and transanal total mesorectal excision in high-volume centres.

BACKGROUND: The routine use of MRI in rectal cancer treatment allows the use of a strict definition for low rectal cancer. This study aimed to compare minimally invasive total mesorectal excision in MRI-defined low rectal cancer in expert laparoscopic, transanal and robotic high-volume centres. METHODS: All MRI-defined low rectal cancer operated on between 2015 and 2017 in 11 Dutch centres were included. Primary outcomes were: R1 rate, total mesorectal excision quality and 3-year local recurrence and survivals (overall and disease free). Secondary outcomes included conversion rate, complications and whether there was a perioperative change in the preoperative treatment plan. RESULTS: Of 1071 eligible rectal cancers, 633 patients with low rectal cancer were identified. Quality of the total mesorectal excision specimen (P = 0.337), R1 rate (P = 0.107), conversion (P = 0.344), anastomotic leakage rate (P = 0.942), local recurrence (P = 0.809), overall survival (P = 0.436) and disease-free survival (P = 0.347) were comparable among the centres. The laparoscopic centre group had the highest rate of perioperative change in the preoperative treatment plan (10.4%), compared with robotic expert centres (5.2%) and transanal centres (2.1%), P = 0.004. The main reason for this change was stapling difficulty (43%), followed by low tumour location (29%). Multivariable analysis showed that laparoscopic surgery was the only independent risk factor for a change in the preoperative planned procedure, P = 0.024. CONCLUSION: Centres with expertise in all three minimally invasive total mesorectal excision techniques can achieve good oncological resection in the treatment of MRI-defined low rectal cancer. However, compared with robotic expert centres and transanal centres, patients treated in laparoscopic centres have an increased risk of a change in the preoperative intended procedure due to technical limitations.

Completion Total Mesorectal Excision: A Case-Matched Comparison With Primary Resection.

Objectives: The aim of this study was to compare the perioperative and oncological results of completion total mesorectal excision (cTME) versus primary total mesorectal excision (pTME). Background: Early-stage rectal cancer can be treated by local excision alone, which is associated with less surgical morbidity and improved functional outcomes compared with radical surgery. When high-risk histological features are present, cTME is indicated, with possible worse clinical and oncological outcomes compared to pTME. Methods: This retrospective cohort study included all patients that underwent TME surgery for rectal cancer performed in 11 centers in the Netherlands between 2015 and 2017. After case-matching, we compared cTME with pTME. The primary outcome was major postoperative morbidity. Secondary outcomes included the rate of restorative procedures and 3-year oncological outcomes. Results: In total 1069 patients were included, of which 35 underwent cTME. After matching (1:2 ratio), 29 cTME and 58 pTME were analyzed. No differences were found for major morbidity (27.6% vs 19.0%; P = 0.28) and abdominoperineal excision rate (31.0% vs 32.8%; P = 0.85) between cTME and pTME, respectively. Local recurrence (3.4% vs 8.6%; P = 0.43), systemic recurrence (3.4% vs 12.1%; P = 0.25), overall survival (93.1% vs 94.8%; P = 0.71), and disease-free survival (89.7% vs 81.0%; P = 0.43) were comparable between cTME and pTME. Conclusions: cTME is not associated with higher major morbidity, whereas the abdominoperineal excision rate and 3-year oncological outcomes are similar compared to pTME. Local excision as a diagnostic tool followed by completion surgery for early rectal cancer does not compromise outcomes and should still be considered as the treatment of early-stage rectal cancer.