ABSTRACT
INTRODUCTION Metastatic triple-negative breast cancer (TNBC) presents a management challenge with a poor prognosis compared to other subtypes of breast cancer. In part, this refl ects the inherent characteristics of TNBC, which is an aggressive, highly proliferative breast cancer with a preponderance of visceral and brain metastases. Most importantly, there is a relative lack of targeted therapy options compared to cancers that express either the oestrogen receptor (ER) or have HER2 amplifi cation. This is compounded by high levels of heterogeneity in the cancers, which in part contributes to the frequently observed clinical pattern of response to chemotherapy being maintained for short durations prior to progression.
