1774 (34·4%) of 5161 patients had hormone receptor-negative, HER2-negative tumours, 1430 (27·7%) had HER2-positive tumours (of whom 858 [60·0%] were hormone receptor-positive and 572 [40·0%] hormone receptor-negative) and 1957 (37·9%) had hormone receptor-positive, HER2-negative tumours. The gene discussed is ERBB2; the disease is neoplasm.