Background: We aimed to evaluate the correlation of neutrophil-to-lymphocyte ratio (NLR) with pathological response, disease-free survival (DFS), and overall survival (OS) in patients with breast cancer and under neoadjuvant chemotherapy (NAC).
Materials and methods: We performed a systematical search using Cochrane Library, ScienceDirect, PubMed, Embase, and Web of Science up to May 2018. On the basis of the data directly obtained from the available studies, the odds ratios (ORs) and their 95% confidence intervals (95% CIs) were pooled on the basis of higher or lower NLR levels.
Results: The meta-analysis showed that high NLR was significantly associated with poor NAC response (OR = 2.27, 95% CI: 1.46-3.53, P < .001) but not with the DFS (OR = 1.18, 95% CI: 0.78-1.78, P = .435) and OS (OR = 2.781, 95% CI: 0.54-14.32, P = .221).
Conclusion: Although high NLR was significantly associated with poor pathological response, we were unable to demonstrate the prognostic value of NLR for DFS and OS in patients with breast cancer who were undergoing NAC.