Morbidity, Mortality, and Pathologic Outcomes of Transanal Versus Laparoscopic Total Mesorectal Excision for Rectal Cancer Short-term Outcomes From a Multicenter Randomized Controlled Trial

Abstract

Objective: To determine the morbidity, mortality, and pathologic outcomes of transanal total mesorectal resection (taTME) versus laparoscopic total mesorectal excision (laTME) among patients with rectal cancer with clinical stage I to III rectal cancer below the peritoneal reflection. Background: Studies with sufficient numbers of patients allowing clinical acceptance of taTME for rectal cancer are lacking. Thus, we launched a randomized clinical trial to compare the safety and efficacy of taTME versus laTME. Methods: A randomized, open-label, phase 3, noninferiority trial was performed at 16 different hospitals in 10 Chinese provinces. The primary endpoints were 3-year disease-free survival and 5-year overall survival. The morbidity and mortality within 30 days after surgery, and pathologic outcomes were compared based on a modified intentiontotreat principle; this analysis was preplanned.

Discordance in TME Specimen Grading in a Prospective Phase II Multicenter Rectal Cancer Trial

“…The wide-ranging variation in reported rates of IC TME raises questions regarding QC measures used to validate the assessment of TME grade in prospective observational and randomized trials 30,31 . Liu et al 30 acknowledged that despite an independent review by an oversight committee, an over-estimation bias for successful resection, based on the TME grading assessed by pathologists at each of the 16 participating institutions, still remains a “certain possibility.” Among 13 prospective and randomized rectal cancer surgical trials published or ongoing, only 7 described pathology QC measures to validate the accuracy of TME specimen grading, (Supplemental File 5, http://links.lww.com/SLA/E739). None of them described how central review was operationalized, or how discrepancies in grading were managed, and in 2 trials, QI measures included a discussion between the site and central reviewer regarding agreement, and education of sites when minimal reporting standards were not met 17,30 (Supplemental File 5, http://links.lww.com/SLA/E739).…”

“…In the first 2 RCTs published to date comparing outcomes of laparoscopic versus taTME in sphincter-saving LAR for rectal cancer, the rate of IC TME was 0% in both trials’ taTME arms, totaling 599 patients. The wide-ranging variation in reported rates of IC TME raises questions regarding QC measures used to validate the assessment of TME grade in prospective observational and randomized trials 30,31 . Liu et al 30 acknowledged that despite an independent review by an oversight committee, an over-estimation bias for successful resection, based on the TME grading assessed by pathologists at each of the 16 participating institutions, still remains a “certain possibility.” Among 13 prospective and randomized rectal cancer surgical trials published or ongoing, only 7 described pathology QC measures to validate the accuracy of TME specimen grading, (Supplemental File 5, http://links.lww.com/SLA/E739).…”

“…Liu et al 30 acknowledged that despite an independent review by an oversight committee, an over-estimation bias for successful resection, based on the TME grading assessed by pathologists at each of the 16 participating institutions, still remains a “certain possibility.” Among 13 prospective and randomized rectal cancer surgical trials published or ongoing, only 7 described pathology QC measures to validate the accuracy of TME specimen grading, (Supplemental File 5, http://links.lww.com/SLA/E739). None of them described how central review was operationalized, or how discrepancies in grading were managed, and in 2 trials, QI measures included a discussion between the site and central reviewer regarding agreement, and education of sites when minimal reporting standards were not met 17,30 (Supplemental File 5, http://links.lww.com/SLA/E739). Regarding the monitoring of the technical competency of TME surgeons, although 12 trials used surgical volume as a prerequisite for site inclusion, only 7 performed video-based assessments of surgical skills and 9 trials incorporated central review or audits of trial TME videos as part of their monitoring plan 37 (Supplemental File 5, http://links.lww.com/SLA/E739).…”

“…Large taTME series and registries report CRM-positive rates ranging from 1.4% to 12.7% 21–25 and rates of IC TME ranging from 1.5% to 11% 24,26–29 . In the first 2 RCTs comparing laparoscopic to taTME, CRM-positive rates varied from 0% to 2.4% with IC TME reported in 0% to 22% 30,31 . The variability in mesorectal grade reported in RCTs raises questions regarding the internal validity of reported TME grades and whether quality control (QC) measures should be systematically implemented in the assessment of this key pathologic endpoint 30,32 .…”

Transanal Versus Laparoscopic TME

“…[5][6][7] In this issue of Annals of Surgery, the Chinese Transanal Endoscopic Surgery Collaborative (CTESC) group report the short-term results of a phase III randomized trial of taTME versus laparoscopic TME (laTME). 8 This study was a multicentered, randomized, phase 3 clinical trial to test the noninferiority of taTME versus laTME at 16 centers across China. The primary endpoint of disease-free survival will be reported in the future, however short-term outcomes including for surgery "success" are reported now.…”