ERBB2 and breast cancer: Among the 156 338 women with a diagnosis made during 2010-15, the adjusted annual breast cancer mortality rates varied substantially across categories of age, screening status, tumour size, number of positive nodes, and tumour grade in both oestrogen receptor positive and oestrogen receptor negative disease, whereas for HER2 status, which was available for women with diagnoses made in this time period, the adjusted annual mortality rate was lower in HER2 positive than HER2 negative disease in both oestrogen receptor positive and oestrogen receptor negative disease (figure S21).