Table 4 Cox regression analysis of predicting factors for freedom from local recurrence in 749 patients with localized clear cell renal cell carcinoma

pT classification

< 0.001

(T1b vs. T1a)

5.46 (1.77–16.85)

0.003

(T2a vs. T1a)

15.94 (5.31–47.91)

< 0.001

(T2b vs. T1a)

43.16 (15.03–123.95)

< 0.001

Age(≥65 vs < 65)

0.75 (0.41–1.34)

0.326

Gender

0.81 (0.50–1.32)

0.396

Fuhrman grade

< 0.001

(II vs. I)

7.10 (2.69–18.69)

0.001

(III vs. I)

21.80 (8.33–57.05)

0.001

(IV vs. I)

36.92 (11.84–115.11)

< 0.001

Smoking history

1.42 (0.89–2.28)

0.146

Hypertension

0.95 (0.58–1.55)

0.827

Diabetes

0.91 (0.45–1.83)

0.782

Tumor necrosis extent

0.424

0% < TN < 20% vs. TN = 0%

1.15 (0.46–2.87)

0.769

TN ≥ 20% vs. TN = 0%

1.60 (0.79–3.23)

0.193

Ki-67 index

0.210

0% < Ki-67 < 10%vs. Ki-67 = 0%

1.79 (0.94–3.44)

0.078

Ki-67 ≥ 10%vs. Ki-67 = 0%

1.17 (0.42–3.23)

0.764

Tumor volume group

< 0.001

17cm³ ≤ V < 40 cm³ vs. V < 17 cm³

5.10 (1.47–17.71)

0.010

40cm³ ≤ V < 134 cm³ vs V < 17 cm³

15.75 (5.28–47.05)

< 0.001

V ≥ 134 cm³ vs V < 17 cm³

44.85 (15.74–127.84)

< 0.001

BMI(≥25 vs < 25)

0.76 (0.45–1.29)

0.313

Sugical approach (open vs laparoscopic)

0.77 (0.47–1.26)

0.294

Surgical modality (partial vs radical nephrectomy)

1.12 (0.70–1.79)

0.650

Tumor location (left vs right kidney)

0.81 (0.51–1.31)

0.061