Table 1.
Baseline characteristics
| Characteristic | Training cohort (n = 1,175) | Validation cohort (n = 5,249) | p value |
|---|---|---|---|
| Age, years, median (range) | 65 (28–87) | 64 (20–93) | 0.0054 |
| Gender, male | 880 (74.9) | 3,791 (72.2) | 0.0647 |
| Tumor size, cm, median (range)* | 22 (2–180) | 50 (1-200) | <0.0001 |
| Number of tumor* | <0.0001 | ||
| Solitary | 1,010 (86.0) | 3,748 (77.9) | |
| Multiple | 165 (14.0) | 1,069 (22.1) | |
| Microscopic vascular invasion* | 303 (25.8) | 1,252 (26.8) | 0.4785 |
| Major vascular invasion* | 30 (2.5) | 235 (4.7) | 0.0013 |
| Direct invasion or perforation* | 9 (0.8) | 197 (3.8) | <0.0001 |
| Nodal involvement* | 5 (0.4) | 87 (1.7) | 0.0006 |
| Distant metastases* | 3 (0.3) | 126 (2.4) | <0.0001 |
| Histologic grade*, a | <0.0001 | ||
| Well differentiated | 161 (14.3) | 1,008 (21.5) | |
| Moderately differentiated | 755 (66.8) | 2,504 (53.5) | |
| Poorly differentiated | 214 (18.9) | 1,069 (22.8) | |
| Undifferentiated | 0 (0) | 98 (2.1) | |
| Cirrhosis*, b | 0.0007 | ||
| No | 555 (47.2) | 966 (53.6) | |
| Yes | 620 (52.8) | 836 (46.3) | |
| Type of resection* | |||
| Minor | 1,121 (95.4) | 2,569 (54.7) | <0.0001 |
| Major | 54 (4.6) | 2,129 (45.3) |