Clinicopathological and Prognostic Significance of Platelet-Lymphocyte Ratio (PLR) in Gastric Cancer: A Meta-Analysis

Background: Systemic inflammatory parameters, such as the elevator PLR (platelet-lymphocyte ratio), have been found to be associated with the prognosis in gastric cancer (GC); however, the results remain controversial. So we aimed to evaluate the prognostic role of the PLR in gastric cancer by conducting this meta-analysis. Methods: We performed a systematic literature search in PubMed, Embase and the Cochrane Library. The hazard ratio (HR) /Odds Ratio (OR) and its 95% confidence (CI) of survival outcomes and clinicopathological parameters were calculated. Results: A total of 38 studies (39 cohorts) with 23,317 GC patients were included in the final meta-analysis. The pooled results showed that elevated PLR was significantly associated with poor overall survival (OS) (HR: 1.37, 95% CI: 1.25-1.51, p < 0.001; I2= 82.10%, Ph < 0.001) and disease-free survival (DFS) (HR 1.52, 95%CI 1.22–1.90, P< 0.001, I2= 88.6%, Ph< 0.001) of GC patients. Furthermore, patients with elevated PLR had a higher risk of lymph node metastasis (OR = 1.33, 95% CI: 1.03–1.70, p=0.027), serosal invasion (T3 +T4) (OR = 1.58, 95% CI: 1.09–1.31, p=0.017) and increased advanced stage (III+IV) (OR = 1.37, 95% CI: 1.00–1.89, p=0.050). Conclusions: This meta-analysis demonstrated that elevated PLR was a prognostic factor for poor OS and DFS, and associated with clinicopathological parameters in patients with GC.