Table 2 CT parameters of enrolled patients

Maximal tumor diameter, cm (%) (R score)

0.472

 ≤4

389.0 (50.1)

293.0 (55.7)

96.0 (38.4)

 >4-<7

387.0 (49.9)

233.0 (44.3)

154.0 (61.6)

Exophytic/endophytic rate (%) (E score)

0.469

 ≥50%

386.0 (49.7)

259.0 (49.2)

127.0 (50.8)

 <50%

254.0 (32.7)

179.0 (34.0)

75.0 (30.0)

 Endophytic

136.0 (17.5)

88.0 (16.7)

48.0 (19.2)

Distance to the collecting system, mm (%) (N score)

< 0.001

 >7

475.0 (61.2)

351.0 (66.7)

124.0 (49.6)

 4–7

79.0 (10.2)

57.0 (10.8)

22.0 (8.8)

 ≤4

222.0 (28.6)

118.0 (22.4)

104.0 (41.6)

Polar location (%) (L score)

0.056

 Entirely above or below the polar line

226.0 (29.1)

164.0 (31.2)

62.0 (24.8)

 Cross the polar line

297.0 (38.3)

204.0 (38.8)

93.0 (37.2)

 >50% crosses the polar line  crosses the axial renal midline or entirely  between the polar lines

253.0 (32.6)

158.0 (30.0)

95.0 (38.0)

RENAL score (%)

0.005

 Low (4–6)

381.0 (49.1)

281.0 (53.4)

100.0 (40.0)

 Intermediate (7–9)

319.0 (41.1)

210.0 (39.9)

109.0 (43.6)

 High (10–12)

76.0 (9.8)

35.0 (6.7)

41.0 (16.4)

CT necrosis (%)

306(39.4)

136(25.9)

170(68.0)

< 0.001

Calcification (%)

46.0 (5.9)

25.0 (4.8)

21.0 (8.4)

0.044

Tumor margin regularity (%)

169.0 (21.8)

48.0 (9.1)

121.0 (48.4)

< 0.001

Peritumoral neovascularity (%)

73.0 (9.4)

19.0 (3.6)

54.0 (21.6)

< 0.001

Pre-contrast phase (IQR)

 TAV-PCP

30.5 (26.0–35.0)

30.0 (26.0–35.0)

31.0 (28.0–35.0)

0.004

 HDT-PCP

11.0 (9.0–14.0)

11.0 (9.0–14.0)

12.0 (9.0–14.0)

0.03

Corticomedullary phase (IQR)

 TAV-CMP

116.0 (86.0-151.8)

119.0 (88.0-156.0)

110.5 (84.8-148.3)

0.062

 TEV-CMP

84.0 (57.0-121.0)

87.0 (60.0-123.3)

78.5 (54.0-78.5)

0.024

 RER-CMP

0.7 (0.4–0.9)

0.7 (0.5-1.0)

0.6 (0.4–0.8)

< 0.001

 HDT-CMP

40.0 (32.0–50.0)

39.0 (32.0–50.0)

42.0 (32.0–50.0)

0.041

Nephrographic phase (IQR)

 TAV-NP

101.0 (82.0-120.0)

104.0 (84.0-125.0)

97.0 (80.0-114.0)

< 0.001

 TEV-NP

70.5 (52.0–90.0)

73.0 (55.0–93.0)

65.0 (48.0–83.0)

< 0.001

 RER-NP

0.6 (0.4–0.7)

0.6 (0.5–0.7)

0.5 (0.4–0.6)

< 0.001

 HDT-NP

27.0 (22.0–34.0)

27.0 (22.0–34.0)

29.0 (21.0–34.0)

0.058

Excretory phase (IQR)

 TAV-EP

81.0 (69.0–95.0)

82.0 (69.0–96.0)

80.0 (68.8–92.3)

0.043

 TEV-EP

50.0 (38.0–63.0)

51.0 (39.0–65.0)

49.0 (36.8–61.0)

0.002

 RER-EP

0.5 (0.4–0.6)

0.5 (0.4–0.6)

0.4 (0.3–0.5)

< 0.001

 HDT-EP

20.0 (16.0–24.0)

19.0 (16.0–24.0)

21.0 (16.0–25.0)

0.006