Table 1 Characteristics of included studies

Adjuvant radiotherapy

 Nussbaum et al. 2016^{a (19)}

USA

RCS

2196/2196

59.5(13.9) ^#

59.4(15.3) ^#

63

62

12.8(12) ^#

12.9(11.5)

Sur + RT/Sur

1338/858

1377/819

50(45–54) ^¶

OS

0.78 (0.71–0.85)

8

 Trovik et al. 2014⁽⁸⁾

Norway

RCS

42/55

61(35–82) ^§

63(15–83) ^§

34

37

19(6–60) ^§

19(4–43) ^§

Sur + RT/Sur

25/17

29/26

 < 50

OS

0.36 (0.18–0.72)

8

MFS

0.42 (0.20–0.88)

LR

0.20 (0.09–0.45)

 Bates et al. 2018⁽¹⁰⁾

USA

RCS

144/336

–

–

–

–

–

–

Sur + RT/Sur

–

–

–

OS

0.42 (0.19–0.90)

7

Zhou et al. 2010⁽¹³⁾

USA

RCS

364/1183

–

–

–

–

–

–

Sur + RT/Sur

–

–

–

OS

0.78 (0.63–0.95)

7

 Lepechoux et al. 2013⁽¹²⁾

France

RCS

56/42

50(21–80) ^§

54(19–77) ^§

40

24

15(6–46) ^§

20(4–60) ^§

Sur + RT/Sur

–

–

50.4(14–62) ^§

OS

0.91 (0.34–1.39)

8

RFS

0.43 (0.20–0.88)

 Chouliaras et al. 2019^{a (21)}

USA

RCS

59/59

58.2(52–70) ^¶

65.8(52–77) ^¶

74.6

71.2

12.5(8.5–20) ^¶

15(8–23) ^¶

Sur + RT/Sur

34/25

32/27

50.4(45, 54.3) ^¶

OS

0.80 (0.47–1.35)

8

RFS

0.70 (0.43–1.14)

LR

0.47 (0.21–1.06)

 Miura et al. 2015^{a† (18)}

USA

RCS

938/3050

–

–

–

–

\(\le 10\)(26.8%)

\(\le 10\)(27.7%)

Sur + RT/Sur

–

–

–

OS

0.79 (0.70–0.90)

8

10–20(34.5%)

10–20(35.0%)

\(\ge 20\)(17.7%)

\(\ge 20\)(18.8%)

Gronchi et al. 2012^{† (17)}

Italy

RCS

101/230

57(48–67) ^¶

35

17(10–26) ^¶

Sur + RT/Sur

Neg/Pos: 305/26

50(36–65) ^§

OS

0.64 (0.41–1.00)

7

RFS

0.57 (0.35–0.92)

MFS

2.38 (1.34–4.42)

Gronchi et al. 2009^{† (16)}

Italy

RCS

88/200

55(47–66) ^¶

35.8

16(10–26) ^¶

Sur + RT/Sur

Neg/Pos: 257/31

50 (36–65) ^§

OS

0.55 (0.35–0.86)

7

RFS

0.65 (0.42–1.01)

MFS

1.47 (0.81–2.68)

Stahl et al. 2017^{† (15)}

USA

RCS

1132/2772

60^§

52.2

16(0.3–90) ^§

Sur + RT/Sur

Neg/Pos: 2593/1422

50.4(45–54.1) ^¶

OS

0.81 (0.70–0.93)

8

Tseng et al. 2011⁽⁹⁾

USA

RCS

373/1130

61.5(14.8) ^#

31.8

15.5(0.5–99.5) ^§

Sur + RT/Sur

Neg/Pos: 660/875

–

OS

0.92 (0.78–1.09)

7

Klooster et al. 2016^{† (20)}

USA

RCS

102/293

63(53–72) ^¶

49

20(12–44) ^¶

Sur + RT/Sur

Neg/Pos: 0/395

–

OS

0.78 (0.58–1.05)

7

Berger et al. 2018⁽²²⁾

USA

RCS

550/2212

62.9(11.2) ^#

39.1

19.9(11.9) ^#

Sur + RT/Sur

Neg/Pos: 1445/1317

–

OS

0.80 (0.68–0.94)

7

Nathan et al. 2009⁽⁵⁾

USA

RCS

254/1365

63^§

37

17(0.5–99) ^§

Sur + (RT + IORT)/Sur

–

–

OS

0.95 (0.78–1.15)

7

Adjuvant chemotherapy

 Datta et al. 2017⁽¹¹⁾

USA

RCS

390/377

\(\le 62\)(72.3%) 63–71(20.0%) \(\ge 72\)(7.7%)

\(\le 62\)(67.1%) 63–71(24.1%) \(\ge 72\)(8.8%)

77.2

78

\(\le 10\)(24.4%) 10–20(48.5%) \(\ge 20\)(27.1%)

\(\le 10\)(23.3%) 10–20(47.6%) \(\ge 20\)(29.1%)

Sur + CT/Sur

180/210

170/207

–

OS

1.30 (1.05–1.61)

8

 Miura et al. 2015^{a‡ (18)}

USA

RCS

1525/1525

55(43–64)

57(48–64)

30.2

29.8

\(\le 10\)(26.8%) 10–20(34.5%) \(\ge 20\)(17.7%)

\(\le 10\)(27.7%) 10–20(35.0%) \(\ge 20\)(18.8%)

Sur + CT/Sur

614/911

629/896

–

OS

1.17 (1.04–1.31)

8

 Klooster et al. 2016^{‡ (20)}

USA

RCS

122/273

63(53–72) ^¶

49

20(12–44) ^¶

Sur + CT/Sur

Neg/Pos: 0/395

–

OS

1.09 (0.83–1.45)

8

 Gronchi et al. 2009^{‡ (16)}

Italy

RCS

182/394

55(47–66) ^¶

35.8

16(10–26) ^¶

Sur + CT/Sur

Neg/Pos: 257/31

–

OS

1.30 (0.86–1.97)

7

RFS

1.34 (0.88–2.05)

MFS

0.72 (0.39–1.24)

 Gronchi et al. 2012^{‡ (17)}

Italy

RCS

218/444

57(48–67) ^¶

35

17(10–26) ^¶

Sur + CT/Sur

Neg/Pos: 305/26

–

OS

1.14 (0.74–1.75)

7

RFS

1.26 (0.80–1.97)

MFS

0.66 (0.36–1.20)

 Stahl et al. 2017^{‡ (15)}

USA

RCS

445/3447

60^§

52.2

16(0.3–90) ^§

Sur + CT/Sur

Neg/Pos: 2593/1422

–

OS

0.82 (0.67–0.99)

8