The Molecular Predictive and Prognostic Biomarkers in Metastatic Breast Cancer: The Contribution of Molecular Profiling

Simple Summary We propose in this article to review the state of knowledge about predictive and prognosis biomarkers in metastatic breast cancer through the prism of molecular profiling studies. The past decade was marked by several important studies deciphering the molecular landscape of metastatic breast cancer. Although the initial goal of these studies was to find driver oncogenic events to explain cancer progression and metastatic spreading, they have also permitted the identification of several molecular alterations associated with treatment response or resistance. Herein, we review validated (PI3KCA, ESR1, MSI, NTRK translocation) and emergent molecular biomarkers (ERBB2, AKT, PTEN, HRR gene, CD274 amplification RB1, NF1, mutational process) in metastatic breast cancer, on the bases of the largest molecular profiling studies. These biomarkers will be classed according the level of evidence and, if possible, the ESCAT (ESMO) classification. Finally, we will provide some perspective on development in clinical practice for the main biomarkers.

Automated summary

This article reviews the knowledge about predictive and prognosis biomarkers in metastatic breast cancer based on molecular profiling studies. It summarizes the findings of important studies deciphering the molecular landscape of metastatic breast cancer and identifies molecular alterations associated with treatment response or resistance. The article also classifies the validated and emergent molecular biomarkers in metastatic breast cancer according to the level of evidence and ESCAT classification, and provides perspective on their development in clinical practice.