ERBB2 and neoplasm: The results revealed that patients with HER2-low had significantly more favorable IDFS and DRFS than patients with HER2-zero in the high recurrence-risk group (i.e., in cohort 1: patients with ≥ 4 positive ALNs, or 1–3 positive ALNs, and either HG 3 or tumor size ≥ 5 cm).