Table 1 Baseline characteristics of the patients
Korea (N = 8,812) | United States (N = 2,717) | p | |
|---|---|---|---|
Age, year | 55.3 ± 12.7 | 60.0 ± 12.1 | < 0.001 |
Sex, No. (%) | < 0.001 | ||
Male | 6,098 (69.2) | 1,744 (64.2) | |
Female | 2,714 (30.8) | 973 (35.8) | |
BMI, kg/m2 | 24.5 ± 5.7 | 29.9 ± 6.8 | < 0.001 |
Creatinine (mg/dL) | 1.08 ± 1.22 | 1.22 ± 0.98 | < 0.001 |
Preop. eGFR, mL/min/1.73m2 | 77.6 ± 33.8 | 68.2 ± 23.4 | < 0.001 |
Race, No. (%) | < 0.001 | ||
Asian | 8,812 (100) | 69 (2.5) | |
Caucasian | 0 | 2125 (78.2) | |
African-American | 0 | 470 (17.3) | |
Others | 0 | 53 (2.0) | |
Missing | 0 | 0 | |
ASA score, No. (%) | < 0.001 | ||
I | 3,363 (38.2) | 20 (0.3) | |
II | 4,151 (47.1) | 938 (44.5) | |
III | 352 (4.0) | 1090 (51.7) | |
IV | 13 (0.1) | 62 (2.9) | |
Missing | 933 (10.6) | 0 | |
Clinical T stage, No. (%) | < 0.001 | ||
T1a | 5,623 (65.8) | 1,358 (50.2) | |
T1b | 1,489 (19.2) | 711 (26.3) | |
T2 | 696 (9.0) | 362 (13.3) | |
T3 | 294 (3.7) | 173 (6.4) | |
T4 | 25 (0.3) | 9 (0.3) | |
Missing | 143 (1.8) | 91 (3.4) | |
Year of Surgery, No. (%) | < 0.001 | ||
− 2000 | 467 (6.0) | 6 (0.2) | |
2001–2005 | 781 (10.1) | 606 (22.3) | |
2006–2010 | 2,744 (35.4) | 928 (34.2) | |
2011–2015 | 3,757 (48.5) | 1177 (43.3) | |
Type of Surgery, No. (%) | 0.639 | ||
Partial nephrectomy | 4,761 (54.0) | 1,454 (53.5) | |
Radical nephrectomy | 4,051 (46.0) | 1,263 (46.5) | |
Surgical Method, No. (%) | < 0.001 | ||
Open | 3,893 (50.2) | 540 (19.9) | |
Laparoscopic | 2,263 (29.2) | 1341 (49.4) | |
Robotic | 1,593 (20.6) | 836 (30.8) | |
Tumor size, cm | 4.0 ± 3.0 | 4.9 ± 3.2 | < 0.001 |
Tumor Size, No. (%) | < 0.001 | ||
≤ 4 cm | 5,295 (68.3) | 1454 (53.6) | |
> 4 cm, ≤ 7 cm | 1,514 (19.5) | 735 (27.1) | |
> 7 cm | 940 (12.1) | 528 (19.4) | |
Histology, No. (%) | < 0.001 | ||
Renal cell carcinoma | 7145 (92.1) | 2316 (85.2) | |
Other malignancy | 127 (1.6) | 13 (0.5) | |
Oncocytoma | 121 (1.6) | 197 (7.3) | |
Angiomyolipoma | 206 (2.7) | 91 (3.3) | |
Other benign tumors | 150 (2.0) | 100 (3.7) |