Molecular signatures in breast cancer: the anatomopathologist's point of view

摘要

The management of breast cancer is primarily based on classic clinical-pathological parameters. With the generalization of mass screening and progress in knowledge of the molecular classification of breast cancer, the intrinsic biology of the tumor makes it possible to refine the therapeutic strategy, in particular in breast cancers expressing hormone receptors and "HER2 negative". If the very high risk of relapse remains undisputedly determined by the clinical stage or the non-response to neoadjuvant treatments, the prediction of hormonal sensitivity is more difficult. The molecular signatures of gene expression will provide strong prognostic data, making it possible to avoid chemotherapy for many patients, and even to identify patients who may benefit from prolonged hormone therapy. These molecular signatures, in a number of cases, encompass grade, Ki67, and stage parameters. Furthermore, in postmenopausal patients with one to three invaded lymph nodes, data from the RxPONDER study show that, for patients with a low risk 21 gene signature (Oncotype DX?), there is no benefit from adjuvant chemotherapy. Pathologists, along with clinicians, can be delighted that they have these tools to help with therapeutic decision-making and therapeutic de-escalation.