Introduction: Prognostic biomarkers are highly needed to properly manage patients with cancer and improve their clinical courses. The relationship between lymphocyte-to-monocyte ratio (LMR) at diagnosis and ovarian cancer prognosis has been extensively studied, but little consensus has been reached regarding its utility as a biomarker of poor outcome. Thus, this study aimed to investigate the potential prognostic value of pretreatment LMR in such patients to shed light on this issue.
Methods: We searched the scientific databases of MEDLINE, Embase, Cochrane Library, and WangFang for relevant studies about the inflammatory prognostic factor LMR in ovarian cancer, based on specific inclusion and exclusion criteria. The following parameters were analyzed among others: LMR values and respective cut-offs, patient's overall survival (OS) and progression-free survival (PFS), and clinicopathological features.
Results: Eight studies, including 2259 patients, were eligible for inclusion in this meta-analysis. We found that low LMR was associated with both poor OS [Hazard ratio (HR): 1.92; 95% confidence interval (CI): 1.58-2.34; p < 0.001] and PFS (HR: 1.70; 95% CI: 1.54-1.88; p < 0.001). Moreover, our findings revealed that low LMR was correlated with high G2/G3 histological grade (OR: 1.67; 95% CI: 1.26-2.20; p < 0.001) and late III-IV FIGO stage tumors (OR: 3.55; 95% CI: 2.68-4.70; p < 0.001), high serum CA-125 level (OR: 2.18; 95% CI: 1.71-2.77; p < 0.001), and presence of malignant ascites (OR: 1.87; 95% CI: 1.11-3.14; p = 0.02) and lymph node metastases (OR: 1.70; 95% CI: 1.13-2.54; p = 0.01).
Conclusion: Pretreatment LMR is a potential prognostic marker of poor outcome in ovarian cancer patients and may thus be important in clinical care and disease control.
Keywords: Lymphocyte-to-monocyte ratio; Meta-analysis; Ovarian cancer; Prognosis.