[Molecular biomarkers in breast cancer : advances in precision medicine].

Breast cancer is a complex disease influenced by genetic and environmental factors. Molecular profiling research has revealed significant diversity within the disease, including among tumours with similar morphological features. This diversity can lead to significant differences in tumour behaviour. Scientists have turned their attention to molecular biomarkers to predict cancer behaviour and/or response to treatment, and to ensure personalised, optimal management of breast cancer patients. This article presents four examples of molecular biomarkers and genetic tests used in the field of breast cancer, highlighting their latest advances and their clinical use as predictive and/or prognostic markers.