Long-term oncological outcomes of robotic versus laparoscopic total mesorectal excision of mid–low rectal cancer following neoadjuvant chemoradiation therapy

Propose: The use of robotic surgery and neoadjuvant chemoradiation therapy (CRT) for rectal cancer is increasing steadily worldwide. However, there are insufficient data on long-term outcomes of robotic surgery in this clinical setting. The aim of this study was to compare the 5-year oncological outcomes of laparoscopic vs. robotic total mesorectal excision for mid–low rectal cancer after neoadjuvant CRT. Materials and methods: One hundred thirty-eight patients who underwent robotic (n = 74) or laparoscopic (n = 64) resections between January 2006 and December 2010 for mid and low rectal cancer after neoadjuvant CRT were identified from a prospective database. The long-term oncological outcomes of these patients were analyzed using prospective follow-up data. Results: The median follow-up period was 56.1 ± 16.6 months (range 11–101). The 5-year overall survival (OS) rate of the laparoscopic and robotic groups was 93.3 and 90.0 %, respectively, (p = 0424). The 5-year disease-free survival (DFS) rate was 76.0 % (laparoscopic) vs. 76.8 % (robotic) (p = 0.834). In a subgroup analysis according to the yp-stage (complete pathologic response, yp-stage I, yp-stage II, or yp-stage III), the between-group oncological outcomes were not significantly different. The local recurrence rate was 6.3 % (laparoscopic, n = 4) vs. 2.7 % (robotic, n = 2) (p = 0.308). The systemic recurrence rate was 15.6 % (laparoscopic, n = 10) vs. 18.9 % (robotic, n = 14) (p = 0.644). All recurrences occurred within less than 36 months in both groups. The median period of recurrence was 14.2 months. Conclusion: Robotic surgery for rectal cancer after neoadjuvant CRT can be performed safely, with long-term oncological outcomes comparable to those obtained with laparoscopic surgery. More large-scale studies and long-term follow-up data are needed.