Table 5 Multivariate Cox regression analyses of overall survival for four molecular subtypes of T1a breast cancer patients in the matched cohort

GRADE

 I

reference

reference

reference

reference

 II

2.21(0.91–5.36)

0.08

-

-

0.55(0.07–4.62)

0.58

-

-

 III

2.92(1.08–7.92)

0.04

-

-

0.35(0.04–3.24)

0.35

-

-

SURGERY

 Breast-conserving

reference

reference

reference

reference

 Total mastectomy

0.46(0.17–1.23)

0.12

22.06(2.09–232.47)

0.01

1.79(0.11–28.43)

0.68

0.44(0.11–1.85)

0.26

 Modified radical mastectomy

0.29(0.07–1.24)

0.09

-

-

1.09(0.04–27.13)

0.96

-

-

RADIATION

 No

reference

reference

reference

reference

 Yes

0.20(0.07–0.58)

 < 0.01

6.33(0.66–60.72)

0.11

1.41(0.09–21.27)

0.80

0.19(0.04–0.85)

0.03

CHEMOTHERAPY

 No

reference

reference

reference

reference

 Yes

2.25(1.09–4.62)

0.66

0.27(0.06–1.25)

0.10

0.51(0.15–1.70)

0.27

0.66(0.21–2.10)

0.48

AGE (year)

 < 60

reference

reference

reference

reference

 ≥ 60

5.22(2.40–11.32)

 < 0.0001

52.09(6.10–444.61)

 < 0.01

1.31(0.37–4.67)

0.68

0.47(0.13–1.77)

0.27