Table 4 Multivariate regression analysis of predictors of pathological complete response (pCR) after primary systemic therapy.

Predictor	Coefficient (SE)	Odds Ratio (95% CI)	P value
* stage cT3 and cT4 were combined in one category; CI = confidence interval; RZT = reference trastuzumab; SE = standard error
Tumor size before NAT (per Stage*)	−0.75 (0.36)	0.48 (0.24–0.96)	0.038
Nodal involvement before NAT
no	0	1
yes	−0.81 (0.46)	0.45 (0.18–1.09)	0.077
Grading
G2	0	1
G3	−0.53 (0.48)	0.59 (0.23–1.52)	0.273
Hormonal receptor status
positive	0	1
negative	1.48 (0.48)	4.37 (1.72–11.13)	0.002
HER2 Status
2+	0	1
3+	0.82 (0.54)	2.27 (0.79–6.53)	0.130
Anthracycline treatment
no	0	1
yes	−0.66 (0.82)	0.52 (0.10–2.56)	0.419
Pertuzumab treatment
no	0	1
yes	1.00 (0.55)	2.71 (0.93–7.96)	0.069
Type of trastuzumab
RZT	0	1
ABP 980	−0.28 (0.48)	0.76 (0.30–1.92)	0.558