Background: Metastatic triple-negative breast cancer (mTNBC) is a heterogeneous disease with poor prognosis where recent studies suggest that the immune system plays a critical role the mechanisms of disease progression and metastasis. In the other hand, a high Neutrophil to Lymphocyte Ratio (NLR) is associated with poor survival in patients diagnosed with several types of cancer. Our aim was to evaluate the prognostic value of NLR in mTNBC.

Methods: We retrospectively reviewed 130 patients diagnosed with mTNBC between 2000-2014 at “Instituto Nacional de Enfermedades Neoplasicas”. NLR group was divided in <2.5 and ≥2.5. Sites of metastasis were identified by TAC or magnetic resonance imaging. Survival rates were estimated by the Kaplan-Meier method and differences were calculated by Log-rank test. The Cox Regression was used for prognostic factors.

Results: The median age was 50 years (range: 23-92 years). From our study population, 41.2% were premenopausal, and just 10 patients (9.5%) had a breast-ovary cancer familiar background, 62.5% were diagnosed at clinical stage T3-T4 and 86.1% had lymph node involvement. From 130 patients, 41 and 64 had NLR <2.5 and ≥2.5, respectively, while there was no association between characteristics and NLR, only patients with malnutrition had NLR ≥2.5 (9.1% vs 40.8%, p=0.002) and solid organ involvement (62.4% vs 81.3%, p=0.04). Furthermore, lung and bone were the most frequent sites of metastasis. Those patients with lower ratio (<2.5) had better response to chemotherapy (p <0.001). With a median follow-up of 6.25 years, at 1-year OS was lower among patients with NLR ≥2.5 (59% vs 20%, HR: 2.77, 95%CI:1.77-4.33, p<0.001). In addition, at univariate analysis malnutrition also showed an impact on OS (HR: 1.79, 95%CI: 1.20-2.67, p=0.005). At multivariate analysis, between age, T stage, N stage, NLR and solid organ involvement, just NLR was the best and only predictor of worse OS (HR: 3.12, 95%CI:1.94-5.03, p<0.001). 

Conclusion: In mTNBC, an NLR ≥2.5 was a strong and accessible biomarker of poor OS. Lower values of NLR could help us to predict chemotherapy response.

Citation Format: Gabriel A. De la Cruz Ku, Zaida Morante, Joseph Pinto, Jhajaira Araujo, Daniel Enriquez, Eduardo Eyzaguirre, Antonella Saavedra, Maria Lujan, Renato Luque, Cesar Rázuri, Hugo Fuentes, Silvia Neciosup, Henry Gómez Moreno. Neutrophil to lymphocyte ratio as strongest predictor of early death in metastatic triple negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 588.