Table 2 Comparison of clinicopathological variables between the year groups

Breast side involvement—no. (%)

Right

336 (50.1)

885 (48.0)

1456 (48.4)

0.62

Left

334 (49.9)

960 (52.0)

1555 (51.6)

Age of first presentation—yrs

47.40 ± 10.34^a

49.12 ± 11.70^b

49.43 ± 12.07^b

< 0.001

Tumor size—cm

2.82 ± 1.69^a

2.91 ± 1.49^a

2.66 ± 1.52^b

< 0.001

T—no. (%)†

≤ 2

376 (54.7)^a

842 (45.0)^b

1576 (52.2)^a

< 0.001

< 2 ≤ 5

283 (41.1)^a

931 (49.8)^b

1327 (43.9)^a

> 5

29 (4.2)^{a, b}

98 (5.2)^b

118 (3.9)^a

N—no. (%)†

≤ 3

532 (77.4)

1419 (76.3)

2319 (76.9)

0.75

<3 < 10

103 (15.0)

269 (14.5)

432 (14.3)

≥ 10

52 (7.6)

172 (9.2)

265 (8.8)

Stage—no. (%)^†

0

16 (3.0)^a

51 (3.2)^a

88 (3.3)^a

< 0.001

1

126 (24.0)^a

300 (19.0)^b

653 (24.8)^a

2

254 (48.4)^{a, b}

787 (49.7)^b

1185 (45.1)^a

3

127 (24.2)^a

426 (26.9)^a

646 (24.6)^a

4

2 (0.4)^a

18 (1.1)^a

58 (2.2)^b

Grade—no. (%)

1

133 (29.9)^a

372 (25.5)^a

433 (17.8)^b

< 0.001

2

255 (57.3)^a

817 (56.1)^a

1399 (57.4)^a

3

53 (11.9)^a

266 (18.3)^b

573 (23.5)^c

Grade of nucleus—no. (%)

1

34 (36.6)^a

39 (25.7)^a

195 (14.1)^b

< 0.001

2

51 (54.8)^a

87 (57.2)^a

580 (42)^b

3

8 (8.6)^a

26 (17.1)^a

606 (43.9)^b

In situ component—no. (%)

Yes

194 (66.9)

1049 (69.6)

1646 (68.2)

0.516

No

96 (33.1)

458 (30.4)

769 (31.8)

Tumor necrosis—no. (%)

Yes

126 (43)^a

697 (47.3)^a

1572 (56)^b

< 0.001

No

167 (57)^a

776 (52.7)^a

940 (37.4)^b

Estrogen receptor—no. (%)

Positive

394 (62.4)^a

1328 (73.4)^b

2181 (77.1)^c

< 0.001

Negative

236 (37.4)^a

475 (26.3)^b

643 (22.7)^c

Unknown

1 (0.2)^a

6 (0.3)^a

4 (0.1)^a

Progesterone receptor—no. (%)

Positive

373 (59.5)^a

1160 (64.3)^b

1047 (72.6)^c

< 0.001

Negative

253 (40.4)^a

636 (35.3)^b

768 (27.2)^c

Unknown

1 (0.2)^{a, b}

8 (0.4)^b

4 (0.1)^a

HER2—no. (%)

Positive

12 (24.4)^{a, b}

433 (31.5)^b

695 (26.8)^a

< 0.001

Negative

22 (44.8)^a

942 (68.5)^b

1894 (73)^c

Unknown

15 (30.6)^a

0^b

5 (0.2)^b

Chemotherapy before surgery—no. (%)

Yes

30 (23.1)^a

106 (23.6)^a

285 (16.1)^b

< 0.001

No

100 (76.9)^a

344 (76.4)^a

1485 (83.9)^b

Invasion type—no. (%)

Vascular

33 (6.1)^a

39 (2.3)^b

24 (0.9)^c

Perineural

24 (4.4)^a

90 (5.4)^a

265 (9.9)^b

< 0.001

Lymphatic

124 (22.8)^a

368 (22)^a

165 (6.2)^b

All

40 (7.4)^a

135 (8.1)^a

628 (23.6)^b

None

208 (38.2)^{a, b}

699 (41.8)^b

929 (34.8)^a

Vascular and perineural

14 (2.6)^a

13 (0.8)^b

18 (0.7)^b

Lymphatic and vascular

67 (12.3)^a

262 (15.7)^a

600 (22.5)^b

Lymphatic and perineural

34 (6.2)^a

65 (3.9)^b

37 (1.4)^c

Axillary management—no. (%)

AND

618 (99.7)^a

1400 (78.7)^b

1536 (53.7)^c

< 0.001

SLNB

2 (0.3)^a

237 (13.3)^b

930 (32.5)^c

AND & SLNB

0^a

143 (8)^b

394 (13.8)^c

Total no. of involved lymph nodes in dissection

5.70 ± 6.56

5.65 ± 6.00

5.95 ± 6.99

< 0.001

Type of operation—no. (%)

Mastectomy

477 (71.8)^a

1138 (61.8)^b

1099 (36.7)^c

< 0.001

BCS

187 (28.2)^a

704 (38.2)^b

1893 (63.3)^c

Site of recurrence—no. (%)

Bone

43 (40.2)^b

121 (36.4)^b

111 (45.5)^a

0.015

Brain

7 (6.5)^a

21 (6.3)^a

18 (7.4)^a

lung

16 (15)^a

60 (18.1)^a

36 (14.8)^a

Liver

8 (7.5)^a

56 (16.9)^b

30 (12.3)^{a, b}

Two organs

26 (24.3)^a

55 (16.6)^a

25 (10.2)^b

Multiple organs

3 (2.8)^a

9 (2.7)^a

7 (2.9)^a

Other organs

4 (3.7)^a,b

10 (3)^b

17 (7)^a