ERBB2 and amenorrhea: Specifically, neither difference in disease-free survival (adjusted hazard ratio [HR], 0.92; 95% CI, 0.70 – 1.20) nor in overall survival (adjusted HR, 1.03; 95% CI, 0.68 – 1.56) were observed between patients with HER2-positive/hormone receptor-negative tumours with or without treatment-induced amenorrhea.