Table 1 Multivariate Cox proportional hazards analysis of (A) standard clinical factors alone, or with (B) the Intrinsic Subtypes in relation to Relapse-Free Survival for the 315-sample combined test set. Size was a binary variable (0 = diameter of 2 cm or less, 1 = greater than 2 cm); node status was a binary variable (0 = no positive nodes, 1 = one or more positive nodes); age was a continuous variable formatted as decade-years. Hazard ratios for Intrinsic Subtypes were calculated relative to the Luminal A subtype. Variables found to be significant (p < 0.05) in the Cox proportional hazards model are shown in bold.

Age, per decade

1.04 (0.90–1.20)

0.64

ER status

0.59 (0.41–0.83)

0.003

Node status

1.41 (0.98–2.04)

0.07

Tumor grade 2 vs. 1

2.41 (1.08–5.36)

0.032

Tumor grade 3 vs. 1

3.98 (1.80–8.82)

0.0007

Size

1.60 (1.31–1.95)

<0.0001

B.

Relapse-Free survival

Variable

Hazard Ratio (95% CI)

p-value

Age, per decade

1.08 (0.94–1.24)

0.29

ER status

0.69 (0.42–1.13)

0.14

Node status

1.35 (0.92–1.98)

0.13

Tumor grade 2 vs. 1

1.88 (0.82–4.32)

0.14

Tumor grade 3 vs. 1

2.58 (1.08–6.12)

0.03

Size

1.59 (1.30–1.95)

<0.0001

Basal-like vs. LumA

2.02 (1.05–3.90)

0.036

HER2+/ER- vs. LumA

3.47 (1.78–6.76)

0.0003

LumB vs. LumA

1.92 (1.07–3.45)

0.028

IFN vs. LumA

1.40 (0.67–2.91)

0.37

Normal-like vs. LumA

1.56 (0.59–4.16)

0.37