Table 3 Multivariate Cox regression analyses (Stepwise procedure)

 ECOG 0

1

 ECOG 1

1.75

1.12–2.73

0.013

 ECOG 2

2.62

1.51–4.53

0.001

 ECOG 3

9.78

4.85–19.73

<0.001

 HER2+/HR+

1

 HER2+/HR−

1.19

0.70–2.04

0.514

 HER2−/HR+

2.49

1.49–4.18

0.001

 Triple negative

5.31

2.97–9.47

<0.001

 0

1

 1 or 2

1.81

1.14–2.86

0.012

 > 2

2.57

1.57–4.21

<0.001

Brain metastases

2.26

1.57–3.25

<0.001

Subcutaneous metastases

1.92

1.22–3.01

0.005

Elevated CA 15-3 (cut-off 30 UI/L)

1.95

1.31–2.93

0.001

Elevated HER2 ECD (cut-off 30 ng/mL)

2.51

1.53–4.12

<0.001

Elevated S100ß (cut-off 0.12 μg/L)

1.93

1.05–3.54

0.033