Table I.
Clinical nodal level involvement according to the primary tumor characteristics.
| Ipsilateral (contralateral) neck node level | |||||||
|---|---|---|---|---|---|---|---|
| Primary tumor characteristics | n | Ia | Ib | II | III | IV | V |
| Subsite | |||||||
| Buccal mucosa | 4 | – | 3 | 3 (1) | 3 | 1 | – |
| Upper gingiva | 7 | – | 5 (2) | 6 (3) | 1 | 1 | – |
| Lower gingiva | 12 | 4 | 6 (2) | 3 (1) | – | – | – |
| Hard palate | 4 | – | 2 | 3 | 1 | – | – |
| Tongue | 16 | 3 | 10 (3) | 11 (2) | 7 (1) | 3 | – |
| Floor of the mouth | 4 | 2 (1) | 3 (2) | 4 (2) | 3 (1) | 2 | – |
| T classification | |||||||
| 1–3 | 19 | 3 | 8 | 12 (1) | 5 (1) | 3 | – |
| 4a | 15 | 3 (1) | 9 (6) | 7 (4) | 5 (1) | 1 | – |
| 4b | 13 | 3 | 12 (3) | 11 (4) | 5 | 3 | – |
| Midline involvement | |||||||
| No | 23 | 1 | 13 (3) | 14 (3) | 2 | 3 | – |
| Yes | 24 | 8 (1) | 16 (6) | 16 (6) | 13 (2) | 4 | – |
| Total | 47 | 9 (1) | 29 (9) | 30 (9) | 15 (2) | 7 | 0 |