Usefulness of Pretreatment Neutrophil to Lymphocyte Ratio in Predicting Disease-Specific Survival in Breast Cancer Patients

PURPOSE: The purpose of this study was to investigate the prognostic impact of pretreatment neutrophil to lymphocyte ratio (NLR) on breast cancer in view of disease-specific survival and the intrinsic subtype. METHODS: We retrospectively studied patients diagnosed with primary breast cancer that had completed all phases of primary treatment from 2000 to 2010. The association between pretreatment NLR and disease-specific survival was analyzed. RESULTS: A total of 442 patients were eligible for analysis. Patients with higher NLR (2.5 ≤NLR) showed significantly lower disease-specific survival rate than those with lower NLR (NLR <2.5). Higher NLR along with negative estrogen receptor status and positive nodal status were independently correlated with poor prognosis, with hazard ratio 4.08 (95% confidence interval [CI], 1.62-10.28), 9.93 (95% CI, 3.51-28.13), and 11.23 (95% CI, 3.34-37.83), respectively. Luminal A subtype was the only intrinsic subtype in which higher NLR patients showed significantly poor prognosis (87.7% vs. 96.7%, p=0.009). CONCLUSION: Patients with an elevated pretreatment NLR showed poorer disease-specific survival than patients without elevated NLR, most evident in the luminal A subtype. Further validation and a feasibility study are required before it can be considered for clinical use.