Improved 5-year survival with robot-assisted resection for locally advanced rectal cancer compared to laparoscopic and open surgery: A real-world cohort study.

Abstract

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. 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. 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). 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.