ERBB2 and cancer: The following women are also eligible providing they fulfil the above criteria, women: undergoing, or planned to receive radiotherapy; receiving anti-human epidermal growth factor receptor 2 (anti-HER2) therapies or ovarian suppression drugs; receiving, or planned to receive an adjuvant CDK4/6i (e.g. abemaciclib); have received neoadjuvant-AET; who have had a previous primary breast cancer (as long as they did not have AET to treat that first cancer).