ERBB2 and breast cancer: Additionally, HR was 1.19 of class I (95% CI: 0.24, 5.97), 2.26 of class II (95% CI: 0.27, 18.86), and 27.30 of class III (95% CI: 6.36, 117.27) compared with pCR group in HER2+ BC (p <0.001) (Figure 4C).