ERBB2 and breast cancer: including 943 patients with node-negative, hormone receptor-positive breast cancer who did not receive systemic therapy, for example, showed that patients with luminal B-like/HER2-negative and luminal B-like/HER2-positive tumours experience a statistically significant deterioration in relapse-free survival (HR 1.40, 95% CI 1.10-1.90 and HR 1.60, 95% CI 1.00-2.50) and breast cancer-specific survival (HR 1.80, 95% CI 1.30-2.60 and HR 2.10, 95% CI 1.20-3.80) when compared with patients with luminal A-like tumours.25