Table 3 Subgroup analyses for patients who underwent or did not undergo nephrectomy

 Grade I

3.23 (1.22–8.53)

0.018

 Grade II

2.04 (1.51–2.75)

< 0.001

 Grade III

3.48 (2.75–4.41)

< 0.001

 Grade IV

1.53 (1.06–2.23)

0.024

 N0

2.94 (2.38–3.64)

< 0.001

 N1

1.71 (1.30–2.25)

< 0.001

 NX

3.03 (1.71–5.35)

< 0.001

 Yes

2.01 (1.25–3.26)

0.005

 No

2.40 (1.99–2.89)

< 0.001

 Unknown

3.13 (1.95–5.04)

< 0.001

 Yes

2.46 (1.87–3.26)

< 0.001

 No

2.43 (2.00–2.95)

< 0.001

 Yes

2.16 (1.43–3.25)

< 0.001

 No

2.46 (2.07–2.94)

< 0.001

 Yes

3.09 (2.05–4.65)

< 0.001

 sNo

2.36 (1.99–2.81)

< 0.001

 Yes

2.50 (2.08–3.01)

< 0.001

 No

2.22 (1.62–3.06)

< 0.001