Harmonizing gene signatures to predict benefit from adjuvant chemotherapy in early breast cancer

Breast cancer is a heterogeneous disease, including different subtypes with their own biology, prognosis, clinical characteristics and treatment. To date, traditional clinical and pathological determinants remain the main factors guiding treatment decision-making; however, the development of multigene assays improved the ability to predict the risk of recurrence in patients with early-stage breast cancer. These tools underwent an extensive independent validation and have already been partly incorporated into clinical practice.

The current article summarizes current evidence for the use of the different genomic assays in clinical practice, their characteristics and validation studies. A few studies comparing available genomic assays revealed that they provide different information with a modest correlation and that they are not interchangeable; other trials are currently ongoing in this setting.

Variability across different gene signatures may be a challenge for the optimal management of the individual patient, hence each assay should be used for the clinical setting in which it has been validated.