Abstract

Breast cancer is a heterogenous disease with various morphological, clinical and molecular features. Traditionally, pathologic parameters and clinical stage of the disease are used to determine indication of adjuvant treatment, however these features are not sufficient to identify the patients that need treatment. Prognostic and predictive biomarkers are needed to develop personalized treatments. Predictive factors are indicators of response to a particular treatment. MammaPrint® (Agendia, Amsterdam, the Netherlands), Oncotype DX® (Genomic Health, Redwood City, CA), Prosigna® (Nanostring technologies, Seattle, WA) and Endopredict® (Myriad Genetics) are gene expression profiles that are used to predict the benefit of adjuvant chemotherapy and provide additional prognostic and/or predictive information. In this review, we discuss the role of gene expression signatures in treatment decision of patients with breast cancer.