ERBB2 and neoplasm: In parallel, multigene signatures prognostic and/or predictive for response to chemotherapy were developed.2,3 Several commercially available prognostic classifiers have been cleared by the Food and Drug Administration for clinical use or endorsed by American Society of Clinical Oncology (ASCO), National Comprehensive Cancer Network (NCCN), and Saint-Gallen guidelines to assist clinicians in making decisions about adjuvant chemotherapy, in particular for patients with HR+/HER2− tumour.