METHODS: Adults with cT1-4a Nx M0 rectal adenocarcinoma within 10 cm of the anal verge were randomized 1 : 1 to L-TME or R-TME at three Korean tertiary centres between July 2011 and February 2016. Pre-specified secondary endpoints were 5-year overall, relapse-free, local recurrence-free, and distant recurrence-free survival. Analyses were on a modified intention-to-treat basis.

RESULTS: Of 295 analysed patients (144 L-TME patients and 151 R-TME patients; median follow-up of 72.6 months), 5-year overall survival (92.6% versus 92.4%; P = 0.838) and relapse-free survival (81.9% versus 83.0%; P = 0.801) were similar. Local recurrence occurred in 4.9% (L-TME) and 1.3% (R-TME); 5-year local recurrence-free and distant recurrence-free survival did not differ (P = 0.076 and P = 0.655). In a post-hoc analysis of 146 patients who received neoadjuvant chemoradiotherapy, 5-year local recurrence-free survival was 98.6% in R-TME patients versus 90.7% in L-TME patients (P = 0.039).

CONCLUSION: R-TME and L-TME produced equivalent 5-year oncological outcomes. A post-hoc analysis suggested improved local control with robotic surgery after neoadjuvant chemoradiotherapy, requiring confirmation in prospectively designed studies.