Prognostic value of peripheral blood lymphocyte-to-monocyte ratio in patients with solid tumors: a meta-analysis

Prognostic value of peripheral blood lymphocyte-to-monocyte ratio in patients with solid tumors: a meta-analysis Jun-Jie Teng,1,3 Jian Zhang,1 Tian-Yi Zhang,1 Shu Zhang,2,3 Bao-Sheng Li1,3 1Department of Radiation Oncology, Shandong Cancer Hospital and Institute, 2Department of Medical Oncology, Shandong Cancer Hospital and Institute, 3School of Medicine and Life Sciences, University of Jinan–Shandong Academy of Medical Sciences, Jinan City, Shandong province, People’s Republic of China Background: Although accumulating evidence suggests peripheral blood lymphocyte-to-monocyte ratio (LMR) could act as a prognosis predictor in various tumors, the prognostic value of LMR still remains controversial. We carried out this meta-analysis to evaluate the association of pre-treatment LMR with survival outcomes in patients with solid tumors.Methods: Eligible studies were collected and extracted by searching PubMed and Embase databases up to June 3, 2015. The pooled hazard ratios (HRs) and their 95% confidence intervals (CIs) were computed to assess the prognostic value of LMR quantitatively.Results: Eighteen studies with a total of 8,377 participants were enrolled in this meta-analysis. Our findings indicated that elevated pre-treatment LMR predicted a significantly favorable overall survival (HR=0.59, 95% CI: 0.53–0.67) and disease-free survival (HR=0.74, 95% CI: 0.68–0.80) in solid tumor patients. Subgroup analyses revealed that enhanced LMR was significantly associated with favorable overall survival in patients with digestive system cancers (HR=0.63, 95% CI: 0.49–0.81), urinary tract tumors (HR=0.66, 95% CI: 0.52–0.84), lung cancer (HR=0.62, 95% CI: 0.54–0.72), and nasopharyngeal carcinoma (HR=0.50, 95% CI: 0.43–0.57).Conclusion: This meta-analysis showed that enhanced LMR may indicate a favorable prognosis in patients with solid tumors. Keywords: LMR, solid tumors, prognosis, meta-analysis