Comparison of robotic and laparoscopic approaches in short- and long-term outcomes of lateral pelvic lymph node dissection for advanced rectal cancer: a Japanese multicenter study

Background Lateral pelvic lymph node dissection (LPND) is a challenging surgical technique with complex anatomy and narrow pelvic manipulation. The outcomes of robotic and laparoscopic surgery for LPND are still unclear. Methods We retrospectively reviewed 169 consecutive patients who underwent rectal cancer surgery with LPND between 2016 to 2023. Patients were divided into two groups according to whether LPND was performed by robotic surgery (R group, n = 40) or laparoscopic surgery (L group, n = 129). Clinicopathological feature and outcomes were compared between groups. Results Frequency of surgery with combined resection of adjacent structures (5.0% vs 19.4%, p = 0.023), frequency of patients with distant metastasis (5.0% vs 19.4%, p = 0.028), and estimated blood loss from bilateral LPND (74 mL vs 132 mL, p = 0.013) were all lower in the R group than in the L group. Type of surgical approach did not correlate with postoperative complications. Median follow-up was 31.0 months (range, 1.0–69.0 months). No patients in the R group experienced local recurrence, compared to 4.6% in the L group. Multivariate analysis revealed laparoscopic surgery (odds ratio 3.687, 95% confidence interval 1.505–6.033; p = 0.004) as an independent predictor of poor relapse-free survival. Conclusions Robotic surgery for LPND appears to have good prognostic value in some, but not all, oncologic cases. However, large prospective studies are desirable to validate these findings.