Efficacy of inferior vesical vessels preservation in lateral lymph node dissection for rectal cancer: Short- and long-term outcomes

Aim: Lateral lymph node dissection (LLD) is performed for rectal cancer, with some cases requiring resection of the inferior vesical vessels (IVV). However, whether preservation or resection of the IVV affects urinary dysfunction (UD) as a major complication or local recurrence (LR) is unclear. Thus, we assessed the effect of IVV resection on the short- and long-term outcomes of rectal cancer. Method: This retrospective cohort study included patients who underwent robotic mesorectal excision with LLD between December 2011 and April 2021. The patients were divided into two groups based on preserved and resected IVV. Postoperative complications, including UD, and long-term outcomes, including cumulative LR and cumulative lateral local recurrence (LLR), were evaluated. Results: Among 340 patients, 298 (87.6%) and 42 (12.4%) were included in the IVV preservation and resection groups, respectively. UD was more frequent (50% vs. 16.8%) in the IVV resection group than in the IVV preservation group (p < 0.01). In the multivariate analysis, IVV and autonomic nervous system resections were significantly associated with UD. The 3-year LR was 4.0% and 5.7% in the IVV preservation and resection groups, respectively (p = 0.99). The 3-year LLR was 2.1% and 0% in the IVV preservation and resection groups, respectively (p = 0.27). Conclusion: IVV resection and autonomic nervous system resection were independent risk factors for UD in robotic LLD. IVV preservation, except in cases of necessity, improves patients' quality of life and has favourable oncological outcomes.