The neutrophil-to-lymphocyte and platelet- to-lymphocyte ratios predict efficacy of platinum-based chemotherapy in patients with metastatic triple negative breast cancer

Chemotherapy with platinum salts is one of the most active treatments for metastatic triple negative breast cancer (TNBC) and biomarkers to predict its effectiveness are urgently needed. In recent years, the neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) have emerged as prognostic biomarkers in many malignancies, but their predictive role in metastatic TNBC patients treated with platinum-based chemotherapy remains unexplored. We performed a retrospective, single center trial to evaluate the association between baseline NLR or PLR and progression free survival (PFS) of metastatic TNBC patients treated with platinum-based therapies. As a control population, we analyzed data from patients with hormone receptor-positive HER2-negative metastatic breast cancer. Among 57 metastatic TNBC patients treated with the carboplatin-paclitaxel or carboplatin-gemcitabine combination, high NLR and PLR were associated with significantly lower PFS at both univariate and multivariable analysis. Conversely, we did not find a significant association between NLR or PLR and the PFS of 148 patients in the control population. Our findings suggest that the NLR and PLR could be predictive of benefit from platinum-containing chemotherapy specifically in metastatic TNBC patients. If validated in larger prospective studies, these easy-to-measure parameters could be combined with emerging predictive biomarkers, such as BRCA 1/2 mutations or tumor infiltrating lymphocytes (TILs), to improve the selection of those patients who are more likely to benefit from platinum-based chemotherapy.