Basal and Triple-Negative Breast Cancers: Impact on Clinical Decision-Making and Novel Therapeutic Options

Since the first application of gene expression profiling to breast cancer almost a decade ago, the molecular subtyping of breast cancer has advanced rapidly from a novel concept to a clinically valuable prognostic, and possibly predictive, classification. This review summarizes the definition of the basal and related triple-negative subtypes of breast cancer, their clinical associations, and effect on outcome and treatment decision-making. Particular emphasis is placed on the clinical implications of basal breast cancer and potential therapeutic options available to oncologists.