Elevated baseline circulating platelet-to-lymphocyte ratio and survival in initial stage Ⅳ gastric cancer patients: A meta-analysis

Background: Systemic inflammatory response (SIR) plays important roles in initiation, promotion and progression of tumor. However, the prognostic role of baseline circulating platelet–to–lymphocyte ratio (PLR) (known as a marker of SIR) in human initial stage Ⅳ gastric cancer (GC) remains controversial. Hence, we performed this meta-analysis to assess the value of it in prognosis prediction for these patients. Materials and methods: We searched PubMed, Embase and EBSCO to identify the studies and computed extracted data with STATA 12.0. Results: A total of 3025 patients with initial stage Ⅳ GC from 13 published studies were incorporated into this meta-analysis. We found that elevated baseline circulating PLR was significantly associated with decreased overall survival (OS), but not with progression–free survival (PFS) in stage Ⅳ GC patients. However, in stratified analyses, high PLR was only associated with worse 1-year and 2-year OS, but not with 3-year or 4-year OS; In addition, it was considerably related with reduced 6-month PFS, but not with 1-year or 2-year PFS. Moreover, high PLR markedly correlated with peritoneal metastasis of GC. Conclusion: Elevated baseline circulating PLR decreased 1-year OS and 6-month PFS in initial stage Ⅳ GC patients, implicating that it is a valuable prognostic index for these patients and modifying the inflammatory responses may have a potential for effective treatment.