ERBB2 and neoplasm: The incidence rate of CNS metastases (number of patients diagnosed with CNS metastases per 100 person-years, i.e., among 100 patients from population 1 followed for 1 year) was 21.8% in HER2-positive tumours (compared with 11.1% in HER2-negative tumours), 32.5% in HR-negative tumours (compared with 9.2% in HR-positive tumours) and 32.7% in triple-negative tumours, respectively.