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Updated: Jan 13, 2026

Robot-assisted Total Mesorectal Excision and Lateral Pelvic Lymph Node Dissection for Locally Advanced Middle-low Rectal Cancer
Published on: February 12, 2022
Improved 5-year survival with robot-assisted resection for locally advanced rectal cancer compared to laparoscopic
Marie Hanaoka1, Hiroyasu Kagawa1, Ataru Igarashi2
1Department of Gastrointestinal Surgery, Institute of Science Tokyo, Bunkyo-ku, Tokyo, Japan.
Aim:
Robot-assisted rectal cancer surgery offers short-term benefits; however, data on its long-term outcomes are lacking. In this study, we aimed to compare the short- and long-term outcomes of open, laparoscopic and robot-assisted rectal resection (ORR, LRR and RARR) for locally advanced rectal cancer using a large real-world database.
Methods:
This multi-centre retrospective cohort study analysed 37,191 patients with clinical T3/T4a rectal cancer from the Japanese Medical Data Vision database (2018-2024). After overlap weighting for baseline balance, the effective sample size was 14,627. The primary outcomes were 5-year overall survival (OS) and relapse-free survival (RFS). The secondary outcomes included peri-operative outcomes.
Results:
After overlap weighting, the total number of patients was 2247, 10,339 and 2041 in the RARR, LRR and ORR groups, respectively. The mean age was 70 years, and 66% were male. The RARR group had the lowest post-operative complication rate (17%), shortest duration of hospital stay (16 days) and lowest 90-day mortality rate and total hospitalisation cost; and the highest 5-year OS (94%) and 5-year RFS (93%) compared with the LRR (5-year OS: 86%, 5-year RFS: 83%; p < 0.001) and ORR (5-year OS: 78%, 5-year RFS: 74%; p < 0.001) groups. RARR was significantly associated with improved OS, whereas higher risks were observed for LRR (hazard ratio [HR]: 2.50) and ORR (HR: 4.69).
Conclusion:
Robot-assisted surgery demonstrated superior short- and long-term outcomes and the lowest total hospitalisation cost compared with other approaches. These results demonstrate the potential of robot-assisted surgery as a new standard of treatment for locally advanced rectal cancer.

