Also the cancer sub-type influences the survival chances,13,14 and the sub-types are categorised according to their hormone receptor status (HR+ or HR-) and to the status of the human epidermal growth factor 2 receptor (HER2+ or HER2−).35Different combinations of the receptor statuses can be grouped further, and we follow the distinction between the Luminal A sub-type (HR+ and HER2-) and all other sub-types of breast cancers. The gene discussed is ERBB2; the disease is breast cancer.