Neutrophil-to-lymphocyte ratio and histological type might predict clinical responses to eriburin-based treatment in patients with metastatic breast cancer.

Background: Metastatic breast cancer (MBC) is generally considered to be incurable. Although many options are available for treating MBC, physicians often encounter difficulties in choosing the most appropriate treatment because the MBCs of individual patients respond differently even to the same treatments. Thus, predictive markers for therapeutic efficacy are urgently needed. Neutrophil- and platelet-to-lymphocyte ratios (NLR and PLR, respectively), have been studied and established as prognostic markers for breast cancer patients but whether either or both of these markers are predictive of treatment responses is still unclear. Herein, we investigated predictive markers for eribulin-based treatment responsiveness in patients with MBC, by examining clinicopathological features, including several markers of immunocompetent cells in peripheral blood.

Methods: Clinicopathological features of the 104 patients with metastatic/Stage IV breast cancer given eribulin-based regimens were investigated in relation to clinical responses to eribulin-based treatments and progression-free-survival (PFS).

Results: Special histological types and high NLR at baseline were independently related to poor clinical responses to the treatments (p = 0.023 and 0.039, respectively). The Cox hazard model revealed that patients with oestrogen receptor (ER)-negative tumours and high NLR, monocyte-to-lymphocyte ratio (MLR) and PLR showed significantly shorter PFS (p = 0.021, 0.005, 0.008 and 0.030, respectively). On multivariate analysis, only ER status and NLR remained independent factors related to PFS (p = 0.011 and 0.003, respectively).

Conclusions: Our data revealed that special histological types and high NLR might be factors related to low responsiveness to eribulin-based regimens in patients with MBC.