ERBB2 and neoplasm: Her2 positivity was associated with pT category (p = 0.041), lymph node metastases (p = 0.049) and tumor differentiation (p = 0.036; Table 4), in particular the percentage of Her2 negative tumors was higher in tumors with lower pT-category and without lymph node metastases as compared to Her2 positive tumors.