| Stage | n | Accuracy (%) | Sensibility (%) | Specificity (%) | PPV (%) | NPV (%) |
| N0 | 8 | 86.7 | 75 | 100 | 100 | 77.7 |
| N1 | 1 | 100 | 100 | 100 | 100 | 100 |
| N2 | 1 | 86.7 | 100 | 85.7 | 33.3 | 100 |
| N3 | 5 | 100 | 100 | 100 | 100 | 100 |