Table 1 Basic characteristics of all studies included in this meta-analysis

Yu

China

2017

207

IRS ≥ 3

IRS

OS

1.86 (1.16–2.98)

1.86

1.16

2.98

Multivariate

Huang

Norway

2015

248

IRS ≥ 7

IRS

OS

0.913 (0.735–1.134)

0.913

0.735

1.134

Multivariate

PFS

1.023 (0.756–1.165)

1.023

0.756

1.165

Multivariate

Mizuno

Japan

2015

81

≥10%

low

OS

1.765 (0.874–2.984)

1.765

0.874

2.984

Univariate

PFS

2.134 (1.103–3.654)

2.134

1.103

3.654

Univariate

Madhuchhanda

USA

2017

124

≥5%

low

OS

1.127 (0.903–1.564)

1.127

0.903

1.564

Univariate

PFS

1.097 (0.874–1.645)

1.097

0.874

1.645

Univariate

Ruscito

Germany

2017

112

IRS ≥ 2

IRS

OS

1.707 (1.012–2.881)

1.707

1.012

2.881

Multivariate

Chen

China

2015

80

≥10%

low

OS

2.684 (1.149–6.249)

2.684

1.149

6.249

Multivariate

Sun

China

2015

100

IRS ≥ 9

IRS

PFS

2.574 (1.297–5.638)

2.574

1.297

5.638

Univariate

Chang

USA

2009

440

> 20%

high

OS

0.92 (0.67–1.27)

0.92

0.67

1.27

Multivariate

DFS

0.79 (0.61–1.02)

0.79

0.61

1.02

Deng

USA

2010

439

≥10%

low

OS

1.27 (1.03–1.56)

1.27

1.03

1.56

NA

DFS

1.77 (1.37–2.29)

1.77

1.37

2.29

Landen

USA

2010

65

> 1%

low

OS

1.39 (0.69–2.80)

1.39

0.69

2.8

Univariate

DFS

2.03 (1.16–3.57)

2.03

1.16

3.57

Wang

China

2012

84

> 50%

high

OS

2.43 (1.12–5.28)

2.43

1.12

5.28

Multivariate

DFS

1.70 (0.77–3.77)

1.7

0.77

3.77

Liebscher

Germany

2013

131

IRS ≥ 4

IRS

OS

2.01 (1.03–3.93)

2.01

1.03

3.93

Multivariate

Kuroda

Japan

2013a

62

> 20%

high

OS

1.63 (0.34–7.89)

1.63

0.34

7.89

Univariate

DFS

1.95 (0.95–4.00)

1.95

0.95

4

Kuroda

Japan

2013b

37

> 15%

low

OS

3.62 (0.47–27.88)

3.62

0.47

27.88

Univariate

DFS

3.97 (0.60–26.19)

3.97

0.6

26.19