Table 3 Cox regression analysis of predicting factors for cancer-specifc survival in 749 patients with localized clear cell renal cell carcinoma

pT classification

< 0.001

(T1b vs. T1a)

3.31 (2.00–5.47)

< 0.001

(T2a vs. T1a)

8.18 (4.99–13.42)

< 0.001

(T2b vs. T1a)

16.75 (10.40–26.97)

< 0.001

Age(≥65 vs < 65)

0.95 (0.69–1.32)

0.757

Gender

0.92 (0.68–1.24)

0.583

Fuhrman grade

< 0.001

(II vs. I)

4.43 (2.82–6.95)

< 0.001

(III vs. I)

9.84 (6.18–15.66)

< 0.001

(IV vs. I)

21.51 (12.08–38.30)

< 0.001

Smoking history

1.28 (0.97–1.69)

0.087

Hypertension

1.02 (0.77–1.37)

0.865

Diabetes

1.02 (0.68–1.52)

0.922

Tumor necrosis extent

0.867

0% < TN < 20% vs. TN = 0%

1.02 (0.58–1.80)

0.941

TN ≥ 20% vs. TN = 0%

1.14 (0.71–1.83)

0.593

Ki-67 index

0.434

0% < Ki-67 < 10%vs. Ki-67 = 0%

1.19 (0.76–1.87)

0.438

Ki-67 ≥ 10%vs. Ki-67 = 0%

1.36 (0.79–2.35)

0.269

Tumor volume group

< 0.001

17cm³ ≤ V < 40 cm³ vs. V < 17 cm³

2.19 (1.22–3.94)

0.009

40cm³ ≤ V < 134 cm³ vs V < 17 cm³

6.53 (4.09–10.42)

< 0.001

V ≥ 134 cm³ vs V < 17 cm³

16.36 (10.57–25.32)

< 0.001

BMI(≥25 vs < 25)

0.92 (0.68–1.24)

0.579

Sugical approach (open vs laparoscopic)

0.96 (0.72–1.27)

0.753

Surgical modality (partial vs radical nephrectomy)

0.92 (0.69–1.22)

0.555

Tumor location (left vs right kidney)

0.79 (0.62–1.00)

0.053