Table 2 Cox regression analysis of predicting factors for overall survival in 749 patients with localized clear cell renal cell carcinoma

pT classification

< 0.001

(T1b vs. T1a)

2.79 (1.86–4.19)

< 0.001

(T2a vs. T1a)

5.56 (3.70–8.36)

< 0.001

(T2b vs. T1a)

12.92 (8.79–18.99)

< 0.001

Age(≥65 vs < 65)

0.93 (0.70–1.23)

0.927

Gender

0.89 (0.69–1.15)

0.362

Fuhrman grade

< 0.001

(II vs. I)

3.62 (2.50–5.25)

< 0.001

(III vs. I)

8.17 (5.57–11.98)

< 0.001

(IV vs. I)

18.08 (11.12–29.40)

< 0.001

Smoking history

1.10 (0.86–1.40)

0.449

Hypertension

1.01 (0.78–1.29)

0.970

Diabetes

1.04 (0.74–1.47)

0.819

Tumor necrosis extent

0.651

0% < TN < 20% vs. TN = 0%

0.86 (0.51–1.45)

0.560

TN ≥ 20% vs. TN = 0%

1.15 (0.77–1.73)

0.504

Ki-67 index

–

0.507

0% < Ki-67 < 10%vs. Ki-67 = 0%

1.13 (0.76–1.68)

0.537

Ki-67 ≥ 10%vs. Ki-67 = 0%

1.29 (0.80–2.09)

0.296

Tumor volume group

< 0.001

17cm³ ≤ V < 40 cm³ vs. V < 17 cm³

2.96 (1.88–4.65)

< 0.001

40cm³ ≤ V < 134 cm³ vs V < 17 cm³

5.08 (3.39–7.60)

< 0.001

V ≥ 134 cm³ vs V < 17 cm³

14.19 (9.80–20.56)

< 0.001

BMI(≥25 vs < 25)

0.93 (0.72–1.21)

0.589

Sugical approach (open vs laparoscopic)

0.945 (0.74–1.21)

0.665

Surgical modality (partial vs radical nephrectomy)

1.25 (0.97–1.60)

0.081

Tumor location (left vs right kidney)

0.79 (0.62–1.00)

0.053