Analysis of presacral tissue structure in LARS and the prevention of LARS by reconstruction of presacral mesorectum with pedicled greater omentum flap graft.

BACKGROUND: The greater omentum has played a unique biological role in regenerative surgery. The aim of our study was to alter the anterior sacral structure by filling the anterior sacral space with the greater omentum and evaluate its effect on the low anterior resection syndrome (LARS) after total mesorectal excision (TME) surgery for low rectal cancer. METHODS: We retrospectively collected clinical data of patients with primary low rectal cancer who underwent TME and ileostomy closure in our hospital from March 2018 to March 2020. Spearman correlation analysis was conducted to analyze the correlation between postoperative mesorectal fascia (MRF) thickness and LARS score. Subsequently, we prospectively used a tipped greater omental flap graft to reconstruct the anterior rectal sacral structures (MRF reconstruction) in 17 patients and compared LARS scores and rectal compliance (RC) at week 12 after closure of the ileostomy in both groups. RESULTS: There were 47 patients with No-MRF reconstruction (31 males, mean age 60.68 ± 9.21 years) and 17 with MRF reconstruction (10 males, mean age 49.82 ± 14.74 years). Correlation analysis indicated that MRF thickness and RC were negatively correlated with LARS severity (p < 0.05). The LARS score of patients with MRF reconstruction at 12 weeks was significantly better than that of those with No-MRF reconstruction (32.97 ± 2.65 vs. 26.94 ± 1.52, p = 0.001), and the RC of MRF reconstruction were lower (2.80 ± 0.55 vs. 3.67 ± 0.38, p = 0.001). In addition, MRF reconstruction and No-MRF reconstruction have the similar incidence of postoperative complications (p = 0.156). No hemorrhage or necrosis of the greater omentum flap was observed in any of the patients. CONCLUSIONS: Greater omentum flap transplantation can significantly improve the symptoms of LARS at 12 weeks after ileostomy closure and we expect it to become a new surgical procedure for the treatment of low rectal cancer.