Overall Survival Advantage of Omentum Preservation Over Omentectomy for Advanced Gastric Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND

Since 1910, omentectomy has been an essential component of radical gastrectomy for advanced gastric cancer. However, researchers have recently questioned the benefit of omentectomy in radical gastrectomy. The aim of this meta-analysis was to compare omentectomy and omentum preservation in gastrectomy for advanced gastric cancer in terms of survival outcomes and short-term outcomes.

METHODS

The PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases were searched. Studies that compared omentum preservation with omentectomy were included. Overall survival (OS) and relapse-free survival (RFS) were analyzed as primary outcomes.

RESULTS

Of 3509 records screened, one randomized clinical trial and five propensity-score matched retrospective studies with 1661 patients were selected. Omentum preservation was associated with improved OS (hazard ratio [HR] = 0.757, 95% confidence interval [CI] = 0.603-0.950, P = 0.016, I = 0%), but not with improved RFS (HR = 0.821, 95% CI = 0.668-1.009, P = 0.060, I = 9%) compared with omentectomy for advanced gastric cancer. Furthermore, less blood loss and shorter operation time were found in the omentum preservation group than in the omentectomy group. Additionally, the rate of peritoneal recurrence, the number of harvested lymph nodes, and the incidences of postoperative complications and ileus were comparable in the two groups.

CONCLUSIONS

Basing on the current literature, gastrectomy with omentum preservation was associated with improved OS and short-term outcomes compared with omentectomy for advanced gastric cancer. Further randomized trials are required to confirm the survival benefit of omentum-preserving gastrectomy.