Moreover, Group BC+EN+ patients presented a lower proliferation index (Ki67%) (14.8 ± 10.4 vs. 24.4 ± 18.7 p < 0.0001) as well as a significantly lower expression of HER2 compared with Group BC+EN− patients (9.8% vs. 28%, p = 0.022). Here, ERBB2 is linked to breast cancer.