The data from POETIC showed that the patients with a low baseline Ki67 (<10%) had a low risk of recurrence (4.3% in HER-2-negative breast cancer, 10.1% in HER-2-positive breast cancer), and those with a high baseline Ki67 (≥10%) with conversion to low Ki67 after 2 weeks of NET had a high recurrence (21.5% in HER-2-negative breast cancer, 15.7% in HER-2-positive breast cancer). This evidence concerns the gene ERBB2 and breast cancer.