Among the patients with HER2-negative breast cancer, 15-year OS was 74% (95% CI: 68–79) in the FEC14 group and 70% (95% CI: 64–75) in the FEC21 group (HR = 0.82, 95% CI: 0.61–1.10, p = 0.19); 15-year EFS was 45% (95% CI: 37–53) in the FEC14 group and 44% (95% CI: 35–52) in the FEC21 group (HR = 0.88, 95% CI: 0.69–1.12; p = 0.30). Here, ERBB2 is linked to breast cancer.