| Variable | Number | |
| Lymph node status | N0 | 32 |
| N | 38 | |
| TNM staging | I | 3 |
| II | 38 | |
| III | 29 | |
| Histological grading | 1 | 9 |
| 2 | 37 | |
| 3 | 24 | |
| Tumor size | T1 | 5 |
| T2 | 47 | |
| T3 | 18 | |
| Age | <50 years | 37 |
| ≥50 years | 33 | |