Prognostic significance of platelet-to-lymphocyte ratio in patients with ovarian cancer: A meta-analysis.

BACKGROUND: The platelet-to-lymphocyte ratio (PLR) has been found to predict clinical outcomes in borderline ovarian tumours and the other genital neoplasms. However, its prognostic value in patients with ovarian cancer remains controversial. The aim of this study was to assess its prognostic value in ovarian cancer.

METHODS: We searched MEDLINE, EMBASE and the Cochrane databases to identify studies evaluating the prognostic significance of pretreatment PLR in ovarian cancer. The end points were overall survival (OS) and progression-free survival (PFS). Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using fixed-effects/random-effects models.

RESULTS: A total of 11 studies comprising 3574 patients with ovarian cancer were included. The random-effects meta-analysis demonstrated that patients with elevated PLR had shorter OS (HR: 1.48, 95% CI: 1.24-1.76, P < .001) and PFS (HR: 1.38, 95% CI: 1.17-1.63, P < .001). The negative prognostic impact of high PLR on OS and PFS remained substantial in Asian populations, patients with PLR ≥ 200 and studies with NOS score ≥ 7.

CONCLUSIONS: Elevated pretreatment PLR could be an unfavourable prognostic factor for clinical outcomes in patients with ovarian cancer.