ERBB2 and neoplasm: In the control group for patients with HER2-ve tumours, there was a median fall of 14.6% (IQR: − 40.8–18.3) in Ki67 (∆Ki672week) (Fig. 2C and Additional file 2: Fig. S2C); 100 patients (16.8%) had Ki67baseline ≥ 10% which dropped to < 10% at 2 weeks.