Existing preclinical and clinical data suggest that the presence of a systemic inflammatory response plays a critical role in the progression of several solid tumors. The derived neutrophil-to-lymphocyte ratio (dNLR) represents an easily determinable marker of systemic inflammation and has been proposed as a potential prognostic marker. The present study was performed to validate and further clarify the prognostic relevance of an elevated pre-treatment dNLR in a large cohort of European breast cancer patients. Data from 762 consecutive female breast cancer patients treated from 1999 to 2004 were evaluated. Disease-free survival (DFS) and overall survival (OS) were assessed using the Kaplan-Meier method. To evaluate the prognostic relevance, univariate and multivariate Cox regression models were performed for each endpoint. Applying receiver operating characteristics (ROC) analysis, the optimal cutoff level for the dNLR was 3. In univariate analysis, a dNLR ≥3 was associated with poor DFS (hazard ratio (HR) 1.87, 95 % confidence interval (CI) 1.28-2.73, p = 0.001) and OS (HR 1.67, 95 % CI 1.07-2.63, p = 0.025). Multivariate analysis revealed a significant association between the elevated dNLR and poor DFS (hazard ratio (HR) 1.70, 95 % CI 1.09-2.65, p = 0.018) but did not show a significant association between the dNLR and OS (HR 1.54, 95 % CI 0.91-2.59, p = 0.106). The present study shows that the pre-treatment dNLR is an independent prognostic factor that could be useful for future individual risk assessment in breast cancer patients.
Keywords: Breast cancer; Derived neutrophil-to-lymphocyte ratio; Inflammation; Prognosis.