ERBB2 and breast cancer: The LN involvement variable resulted to be significantly higher in patients who developed later recurrences (p < 0.0001) and discriminated among molecular subtypes (p < 0.0001) separating luminal A from luminal B (p < 0.0001), and luminal A from HER2 positive (non-luminal) (p < 0.0001) and HER2 positive (non-luminal) from TN BC (p < 0.0001).