ERBB2 and neoplasm: Pathologic tumour features associated with SI were: T2 stage (122 (73%) vs. 32 (25%), p < 0.001), N1 stage (76 (45%) vs. 4 (3%), p < 0.001), ER negative status (38 (23%) vs. 8 (6%), p < 0.001), HER2-positive status (33 (20%) vs. 4 (3%), p < 0.001), triple negative tumours (28 (17%) vs. 8 (6%), p = 0.007), grade 3 (80 (48%) vs. 18 (14%), p < 0.001) and positive lympho-vascular invasion (24 (14%) vs. 3 (2%), p < 0.001).