Table 1.
AJCC tumor- (T-) staging and “high-risk” features.
| Designation | Description |
|
| |
| TX | Primary tumor cannot be assessed |
| T0 | No evidence of primary tumor |
| Tis | Carcinoma in situ |
| T1 | Tumor 2 cm or less in greatest dimension with fewer than 2 high-risk features |
| T2 | Tumor >2 cm in greatest dimension or tumor of any size with two or more high-risk features |
| T3 | Tumor with invasion of maxilla, mandible, orbit, or temporal bone |
| T4 | Tumor with invasion of skeleton (axial or appendicular) or perineural invasion of skull base |
|
| |
| High-risk features | |
|
| |
| Depth/invasion | >2 mm, |
| Clark level ≥ IV, or | |
| perineural invasion | |
| Anatomic location | Primary site ear |
| Primary site hair-bearing lip | |
| Differentiation | Poorly differentiated or undifferentiated |