Table 2 Patient clinical and pathologic characteristics

Age at surgery (median)

77 (75–89)

76 (75–79)

82 (80–89)

< 0.001

Gender, n (%)

0.907

 Man

112 (67.5)

88 (67.7)

24 (66.7)

 Woman

54 (32.5)

42 (32.3)

12 (33.3)

BMI (mean ± SD)

21.5 ± 1.8

21.3 ± 2.5

21.6 ± 1.6

0.536

KPS score < 80, n (%)

23 (13.9)

15 (11.5)

8 (22.2)

0.016

Number of underlying diseases, n (%)

0.019

 < 2

106 (63.9)

89 (68.5)

17 (47.2)

 ≥ 2

60 (36.1)

41 (31.5)

19 (52.8)

Presenting symptom, n (%)

25 (15.1)

19 (14.6)

6 (16.7)

0.761

Baseline eGFR (ml/min)

70.5 ± 9.7

72.1 ± 5.9

63.1 ± 6.4

< 0.001

Postoperative eGFR (ml/min)

61.7 ± 8.8

63.3 ± 5.4

52.1 ± 5.6

< 0.001

Tumor size (median)

5.1 (1.8–13)

5.0 (2.5–12.6)

5.3

0.314

Tumor location, n (%)

0.831

 Left

85 (51.2)

66 (50.8)

19 (52.8)

 Right

83 (48.8)

64 (49.2)

17 (47.2)

Surgery procedure, n (%)

0.772

 Open

12 (7.2)

9 (6.9)

3 (8.3)

 Laparoscopic

154 (92.8)

121 (93.1)

33 (91.7)

Surgery method

0.097

 Radical

115 (69.3)

86 (66.2)

29 (80.6)

 Partial

51 (30.7)

44 (33.8)

7 (19.4)

 RENAL score (partial)

0.471

  ≤ 9

39 (76.5)

33 (75.0)

6 (85.7)

  > 9

12 (23.5)

11 (25.0)

1 (14.3)

 Pathological type

0.960

  Clear cell carcinoma

144 (86.7)

113 (86.9)

31 (86.1)

  Papillary

11 (6.6)

8 (6.2)

3 (8.3)

  Chromophobe

6 (3.6)

5 (3.8)

1 (2.8)

  Others

5 (3.0)

4 (3.1)

1 (2.8)

ISUP grade, n (%)

0.595

 Low grade ≤ 2

95 (57.2)

73 (56.2)

22 (61.1)

 High grade ≥ 3

71 (42.8)

57 (43.8)

14 (38.9)

Tumor necrosis, n (%)

29 (17.5)

21 (16.2)

8 (22.2)

0.724

Sarcomatoid differentiation, n (%)

26 (15.7)

19 (14.6)

7 (19.4)

0.481

Lymph node metastasis, n (%)

8 (4.8)

6 (4.6)

2 (5.6)

0.816

Pathological T stage, n (%)

0.794

 T1

134 (80.7)

105 (80.8)

29 (80.6)

 T2

21 (12.7)

17 (13.1)

4 (11.1)

 T3

9 (5.4)

7 (5.4)

2 (5.6)

 T4

2 (1.2)

1 (0.8)

1 (2.8)