Table 5 Odds ratio (OR) and 95% confidence interval (CI) for axillary lymph node metastasis

Age (y)

 > 50

Ref.

Ref.

 ≤ 50

3.67 (1.04–12.99)

0.044

12.73 (1.18–137.51)

0.036

Palpable mass or bloody nipple discharge

 No

Ref.

Ref.

 Yes

1.90 (0.71–5.10)

0.203

0.95 (0.22–4.10)

0.940

Clinical tumor size, median (range), cm

1.18 (0.96–1.45)

0.114

1.44 (0.99–2.08)

Suspicious axillary lymph node on radiologic evaluation

 No

Ref.

Ref.

 Yes

9.07 (3.10–26.52)

< 0.001

9.31 (2.06–41.99)

0.004

Suspicious microcalcification on radiologic evaluation

 No

Ref.

Ref.

 Yes

1.08 (0.37–3.13)

0.891

4.14 (0.45–37.83)

0.208

Nuclear grade^*,†

0.525

0.290

 Low

Ref.

Ref.

 Intermediate

2.06 (0.25–17.10)

0.505

2.93 (0.20–42.43)

0.431

 High

3.21 (0.37–28.26)

0.293

11.14 (0.40–308.25)

0.155

Comedo necrosis^*,†

 No

Ref.

Ref.

 Yes

1.00 (0.29–3.50)

0.998

0.41 (0.06–2.71)

0.357

Hormone receptor^§

 Negative

Ref.

Ref.

 Positive

1.55 (0.43–5.54)

0.503

0.42 (0.03–5.19)

0.498

HER2^§

 Negative

Ref.

Ref.

 Positive

0.27 (0.06–1.23)

0.090

0.30 (0.04–2.59)

0.276

Ki-67 (%) ^§

 < 14%

Ref.

Ref.

 ≥ 14%

1.58 (0.56–4.47)

0.385

0.62 (0.07–5.84)

0.676