Predictive value of prognostic nutritional index in patients undergoing gastrectomy for gastric cancer: A systematic review and meta-analysis

The value of prognostic nutritional index (PNI) in gastrectomy remains controversial. This meta-analysis aimed to evaluate the predictive value of PNI in patients undergoing gastrectomy for malignancy. We retrieved studies from medical literature databases to analyze the endpoints of overall survival, cancer-specific survival, recurrence-free survival, and clinicopathologic features. The hazard ratio (HR) and 95% confidence interval (CI) were used to access the survival prognostic value of PNI in patients after gastrectomy. Odds ratio and mean difference were used to evaluate the relationship between the low PNI and clinicopathologic features. In total, we included 38 articles (39 trial comparisons) which contained 23,756 gastrectomy patients. The results showed that low PNI was associated with shorter overall survival (HR: 1.82, 95% CI 1.62-2.03), shorter cancer-specific survival (HR: 1.44, 95% CI 1.24-1.67), and shorter recurrence-free survival (HR: 2.52, 95% CI 1.41-4.47). Besides, patients with low PNI had a higher risk of postoperative complications compared with high PNI (HR: 1.65, 95% CI 1.30-2.09). And low PNI group was found to be related to older, lower BMI, larger tumor size, deeper tumor invasion, poorer differentiation, more advanced tumor stage, total gastrectomy, and the presence of lymph node metastasis, lymphatic invasion, and vessel invasion. PNI was significantly associated with survival and postoperative complications of gastric cancer patients undergoing gastrectomy. Therefore PNI has the potential to be a prognostic predictor for gastrectomy.