Table 1 Demographic information

Average age (year)

45.4 ± 7.8

47.1 ± 8.3

48.4 ± 9.8

0.885*

0.416

Tumor location

10.258^#

0.247

 Upper outer quadrant

18

21

26

 Lower outer quadrant

5

3

0

 Upper inner quadrant

3

4

3

 Lower inner quadrant

1

0

1

 Central area

3

2

0

Clinical stage

2.018^#

0.732

 I

8

8

6

 II

18

15

16

 IIIA

4

7

8

Pathological type

3.000^#

0.558

 Infiltrating ductal carcinoma

29

29

29

 Mucinous carcinoma

1

1

0

 Medullary carcinoma

0

0

1

ER

1.348^#

0.510

 Positive

19

20

23

 Negative

11

10

7

PR

0.098^#

0.952

 Positive

20

19

20

 Negative

10

11

10

HER-2

4.229^#

0.121

 Positive**

3

8

3

 Negative^##

27

22

27

Surgical approach

4.488^#

0.344

 Modified radical mastectomy

20

25

18

 Endoscopic subcutaneous mammary resection + axillary lymph nodes dissection + reconstruction with implants

9

4

11

 Breast-conserving surgery + axillary lymph nodes dissection

1

1

1