The platelet-to-lymphocyte ratio as a predictor of patient outcomes in ovarian cancer: a meta-analysis

Abstract

Objectives: The platelet-to-lymphocyte ratio (PLR) is a predictive clinical biomarker for different cancers. However, the results of several studies investigating the association between the PLR and the prognosis of ovarian cancer have been inconclusive. Therefore, there is a need to conduct a meta-analysis to estimate the prognostic value of the PLR in ovarian cancer. Methods: We searched the EMBASE, Medline, PubMed, and Web of Science databases to identify clinical studies that had evaluated the association between the PLR and ovarian cancer prognosis. Outcomes evaluated included overall survival (OS) and progression-free survival (PFS). We also analyzed PLR differences between malignant ovarian masses and the controls. Results: Twelve relevant studies that comprised 2340 patients were selected for the meta-analysis. The results revealed that elevated PLR was significantly associated with poor OS (hazard ratio (HR) 1.63, 95% confidence interval (CI) 1.05–2.56, p < 0.01) and PFS (HR 1.61, 95% CI 1.03–2.51, p < 0.01). The PLRs in malignant cases were higher than in controls (mean difference = 63.57, 95% CI 39.47–87.66, p < 0.00001). Conclusion: An elevated PLR is associated with poor prognosis in patients with ovarian cancer. The PLR could be employed as a prognostic marker in patients with ovarian cancer.