Table 1 Patients characteristics and univariate analysis of prognostic factors for survival

 Age (y)

 ≤ 35

134

76.0

70.4

0.020^*

74.4

66.4

0.113

 > 35

934

85.4

82.7

80.5

67.4

Menopausal status

 Premenopausal

697

81.8

79.3

0.026^*

80.3

68.9

0.589

 Postmenopausal

371

89.0

85.1

78.7

63.4

Tumor size

 T1-2

916

86.4

83.6

<0.001^*

81.8

70.9

<0.001^*

 T3-4

97

70.2

70.2

61.2

36.1

 Unknown

55

No of positive lymph nodes

 pN1 (1–3)

780

88.7

86.1

<0.001^*

86.1

77.7

<0.001^*

 pN2 (4–9)

183

77.0

73.0

69.7

51.0

 pN3 (≥ 10)

105

60.6

53.8

49.9

20.8

Lymph node ratio

 < 0.20

690

90.2

87.7

<0.001^*

87.1

78.6

<0.001^*

 0.21-0.65

269

78.6

74.9

75.1

60.9

 > 0.65

109

57.5

52.3

44.3

21.5

ER status

 Positive

599

85.9

84.4

0.008^*

83.9

69.0

<0.001^*

 Negative

393

81.0

76.7

72.2

64.2

 Unknown

76

PR status

 Positive

652

85.9

83.4

0.008^*

83.0

72.6

<0.001^*

 Negative

340

80.3

77.6

72.3

57.0

 Unknown

76

HER-2-neu status

 Positive

321

81.8

79.7

0.077

75.6

66.2

0.026^*

 Negative

585

85.5

82.0

82.7

71.2

 Unknown

162

Chemotherapy regimen

 CMF

142

82.1

79.6

0.332

76.0

60.1

0.069

 Anthracycline and/or taxane

850

84.9

81.9

81.5

71.0

 None/unknown

76

Hormone therapy

 Yes

718

85.7

82.5

0.032^*

83.7

70.5

<0.001^*

 None

350

81.4

78.8

71.2

60.4