Table 1 Clinicopathologic characteristics of study subjects

Mean age

45.5 (22 ~ 73)

Menopausal status

 Pre-menopause

411 (70.5 %)

 Post-menopause

148 (25.4)

 Unknown

24 (4.1 %)

Tumor size

 ≤2 cm

333 (57.1 %)

 >2 cm

250 (42.9 %)

Axillary nodal status

 Node positive (micro- & macro-metastasis/isolated tumor cell)

223 (38.3 %)

 Node negative

360 (61.7 %)

AJCC stage

 I

247 (42.4 %)

 II

272 (46.7 %)

 III

64 (10.9 %)

Histologic type

 Ductal carcinoma

522 (89.5 %)

 Lobular carcinoma

17 (2.9 %)

 Others

44 (7.6 %)

Progesterone receptor

 Positive

383 (65.7 %)

 Negative

198 (34.0 %)

 Unknown

2 (0.3 %)

HER2

 Positive

86 (14.7 %)

 Negative

328 (56.3 %)

 Unknown

169 (29 %)

Nottingham Histologic Score

 1

78 (13.4 %)

 2

314 (53.9 %)

 3

122 (20.9 %)

 Unknown

69 (11.8 %)

Ki-67

 High (≥10 %, or ≥14 %)^a

120 (20.6 %)

 Low (<10 %, or <14 %)^a

425 (72.9 %)

 Unkonwn

38 (6.5 %)

Surgery-Breast

 Mastectomy

308 (52.8 %)

 Breast conservation^b

275 (47.2 %)

Surgery-Axilla

 SLNBx^c Only

19 (3.3 %)

 ALND^d

557 (95.5 %)

 Others

7 (1.2 %)

Adjuvant treatment

 Radiotherapy

197 (33.8 %)

 Chemotherapy

307 (52.7 %)