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.