Table 2.

Cox model multivariable analysis of breast cancer DSS among ER+, tamoxifen-treated women, incorporating standard clinicopathologic factors and (A) intrinsic subtype or (B) ROR-S, as determined by PAM50 qRT-PCR measurements

Clinical endpointMultivariable DSS (0-5 y of follow-up)Multivariable DSS (5 y to end of follow-up)
Hazard ratio (95% CI)PHazard ratio (95% CI)P
A. Intrinsic subtype
    Age1.02 (0.99-1.05)0.26651.00 (0.98-1.02)0.9786
    Grade (1-2 vs 3)1.51 (0.87-2.60)0.14051.05 (0.71-1.56)0.8109
    Lymphovascular invasion1.02 (0.58-1.81)0.94211.16 (0.77-1.75)0.4852
    HER2 (IHC)1.50 (0.77-2.91)0.23140.82 (0.40-1.69)0.5968
    Node status (0 as reference group)<0.00010.0012
        1-32.07 (0.95-4.54)1.54 (0.96-2.47)
        4+5.80 (2.64-12.71)2.78 (1.60-4.82)
    Tumor size (T1 as reference group)0.0490.0002
        T21.22 (0.71-2.09)1.62 (1.08-2.42)
        T33.92 (1.50-10.22)5.11 (1.78-14.62)
        T41.31 (0.38-4.50)4.02 (1.85-8.74)
    Subtype (luminal A as reference group)0.00180.0381
        Luminal B1.99 (1.09-3.64)1.70 (1.13-2.55)
        HER2 enriched3.65 (1.64-8.16)1.52 (0.72-3.18)
        Basal-like17.71 (1.71-183.33)NA
B. ROR-S
    Age1.02 (0.99-1.05)0.26761.00 (0.98-1.02)0.9089
    Grade (1-2 vs 3)1.36 (0.79-2.36)0.26741.01 (0.68-1.51)0.9588
    Lymphovascular invasion0.95 (0.54-1.66)0.8521.18 (0.78-1.79)0.4299
    HER2 (IHC)1.46 (0.77-2.77)0.24670.87 (0.43-1.77)0.6964
        Node status (0 as reference group)<0.00010.0014
        1-32.14 (1.00-4.60)1.55 (0.97-2.48)
        4+6.03 (2.79-13.05)2.78 (1.59-4.86)
    Tumor size (T1 as reference group)0.06470.0003
        T21.19 (0.70-2.05)1.64 (1.10-2.45)
        T33.34 (1.32-8.43)3.69 (1.30-10.46)
        T40.90 (0.25-3.19)4.44 (2.01-9.78)
    ROR-S (low as reference group)<0.00010.0388
        Med2.04 (0.89-4.66)1.86 (1.15-3.00)
        High6.48 (2.56-16.40)1.57 (0.71-3.46)

NOTE: P values for multilevel categorical variables are derived from likelihood ratio tests between models with and without each these variables.

Abbreviation: 95% CI, 95% confidence interval.