Collaborative Stage for TNM 7 - Revised 11/09/2009 [ Schema ]
| Code | Description |
| 000 | None; no perineural invasion present |
| 010 | Perineural invasion present |
| 988 | Not applicable: Information not collected for this case |
| 998 | No histologic examination of primary site |
| 999 | Unknown Not documented in patient record |