What’s Positive About ‘Triple-Negative’ Breast Cancer?

Abstract

Our understanding of the molecular heterogeneity and pathogenesis of breast cancer has led to significant improvements in patients’ survival. The observation of steroid hormone dependence has led to the successful implementation of tamoxifen, aromatase inhibitors and other estrogen receptor modulators in both the adjuvant and advanced setting. Similarly, the observation of HER2 amplification and the successful targeting of HER2 with trastuzumab, and more recently lapatinib, have improved the outcome for this subgroup of patients as well. Still, there is a group of women that represent approximately 15–20% of breast cancer diagnoses that do not demonstrate evidence of estrogen receptor or progesterone receptor expression, or HER2 amplification, which often has an aggressive clinical course dictated, not only owing to its underlying biology, but also due to the lack of treatment options available other than chemotherapy. Recent advances in our ability to analyze clinical tissue has allowed for genome-wide screening in an attempt to identify the driving molecular alterations in this subgroup. These studies are increasing our understanding of this group and are leading to the integration of new therapeutic approaches in this disease. In reality, the classification of ‘triple-negative’ defines this group by the absence of something ‘positive’. Here, we will review the current molecular understanding of ‘triple-negative’ breast cancer and highlight current clinical research in this challenging group of patients.

Keywords:

• basal-like
• breast cancer
• targeted therapy
• triple negative

Financial & competing interests disclosure

Dr Finn and Dr Hurvitz are both recipients of NIH-LRP Awards. Dr Finn has served as a consultant and received research funding from Bristol-Myers Squibb and Glaxo-Smith Kline. He has received honoraria from Genentech. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

Dr Finn and Dr Hurvitz are both recipients of NIH-LRP Awards. Dr Finn has served as a consultant and received research funding from Bristol-Myers Squibb and Glaxo-Smith Kline. He has received honoraria from Genentech. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.