Neoadjuvant Therapy for Breast Cancer as a Model for Translational Research

Abstract

Neoadjuvant therapy, where patients receive systemic therapy before surgical removal of the tumour, can downstage tumours allowing breast-conserving surgery, rather than mastectomy. In addition to its impact on surgery, the neoadjuvant setting offers a valuable opportunity to monitor individual tumour response. The effectiveness of standard and/or potential new therapies can be tested in the neoadjuvant pre-surgical setting. It can potentially help to identify markers differentiating patients that will potentially benefit from continuing with the same or a different adjuvant treatment enabling personalised treatment. Characterising the molecular response to treatment over time can more accurately identify the significant differences between baseline samples that would not be identified without post-treatment samples. In this review, we discuss the potential and challenges of using the neoadjuvant setting in translational breast cancer research, considering the implications for improving our understanding of response to treatment, predicting therapy benefit, modelling breast cancer dormancy, and the development of drug resistance.

Keywords: Breast cancer dormancy; clinical model; drug resistance; neoadjuvant therapy.

Figure 1.

Opportunities for using sequential patient-matched samples for studying response to therapy and predicting therapy benefit in breast cancer. Vertical arrows represent the normal and potential additional (italics) opportunities when sequential patient-matched samples can be taken during a standard treatment regimen (A), during neoadjuvant therapy (B), and during extended neoadjuvant therapy, which could serve as a novel clinical model to investigate treatment-induced dormancy and acquired resistance (C).