Prognostic role of plasma IL-17a expression and neoadjuvant therapy efficacy in breast cancer

Background Breast cancer (BC) is a common and highly malignant disease. Recently, IL-17a was found to be associated with several human malignancies. This study aims to investigate plasma IL-17a expression in BC and explore its role in disease progression and its interaction with neoadjuvant therapy efficacy. Methods Plasma IL-17a expression in BC tissue samples from 54 patients who received neoadjuvant therapy were analyzed and assessed using immunohistochemistry. Results Statistical analysis showed that a high expression of IL-17a before and after neoadjuvant therapy was positively correlated to poor responses (stable disease and progressive disease) (SD + PD). Conversely, IL-17a was significantly decreased in patients with good responses (complete response and pathologic partial response) (CR + PR) compared with patients with poor responses. Moreover, IL-17a was more easily decreased in patients with earlier stages. Furthermore, plasma IL-17a was positively correlated with poor prognosis (PFS) after treatment. Conclusions IL-17a is a potential biomarker of neoadjuvant therapy for BC.