Association of the neutrophil-to-lymphocyte ratio with brain metastases in Hispanic breast cancer patients.

Background: Breast cancer (BC) is one of the most common cancers and leading cause of cancer-related deaths in women. Metastatic disease, particularly brain metastases (BM), is associated with death in BC patients. The neutrophil-to-lymphocyte ratio (NLR) has been associated with BC prognosis, but it is not usually used in clinical practice and has not been associated with BM. We aimed to determine if there is an association between NLR and BM and if NLR is associated with survival in a Hispanic population. Methods: A retrospective cohort with a total of 2,104 patients with a confirmed diagnosis of BC at a single referral center were randomly divided into training and validation datasets. Univariable and multivariable analyses were performed to study the association of NLR with BM and/or survival. Results: No significant differences between datasets were identified. A high NLR (> 2.2) was associated with a higher frequency of BM after multivariable adjustment in both datasets. Overall survival was shorter in patients with a high NLR; however, the most important factor associated with outcome was the presence of BM. The interaction NLR/BM was not statistically significant. Conclusion: A high NLR at BC diagnosis was associated with a higher frequency of BM, and the presence of BM was associated with worse overall survival in Hispanic BC patients.