Regarding the HER2 expression, all HER2-overexpression tumours were positive as expected, but less than half of luminal B (4/11 cases, 36.4 %) and luminal A (7/21 cases, 33.3 %) expressed HER2, and there was no HER2-positive TNCMC (P < 0.001, Chi-square test) (Table 3). Here, ERBB2 is linked to neoplasm.