Prognostic role of neutrophil-lymphocyte ratio in multiple myeloma: a dose-response meta-analysis.

Background: The neutrophil-lymphocyte ratio (NLR), a biomarker for systematic inflammation, has been recently identified as a prognostic factor for various types of both solid and hematologic malignancies. Our study presented here was the first meta-analysis assessing the prognostic role of NLR in multiple myeloma (MM).

Methods: We systematically searched PubMed, Embase, and ISI Web of Science for relevant studies. Odds ratios (ORs) or hazards ratios (HRs) with corresponding 95% CIs are pooled to estimate the association between NLR and clinicopathological parameters or survival of MM patients.

Results: Seven trials with 1,971 MM patients were enrolled in the meta-analysis, and the results indicated that elevated pretreatment NLR was significantly associated with advanced tumor stages (International Staging System [ISS] III vs ISS I-II: OR 2.427, 95% CI: 1.268-4.467; and Durie-Salmon III vs Durie-Salmon I-II: OR 1.738, 95% CI: 1.133-2.665). Moreover, increased NLR also predicted poorer overall survival (HR 2.084, 95% CI: 1.341-3.238) and progression-free survival (HR 1.029, 95% CI: 1.016-1.042). And two-stage dose-response meta-analysis revealed linear association between increased NLR and risk of mortality in MM patients.

Conclusion: We can conclude that MM patients with higher NLR are more likely to have poorer prognosis than those with lower NLR.