Table 4.
Microscopic features
| Microscopic characteristic | Number (n = 86) |
|---|---|
| Derivation | |
| Possible surface epithelial involvement | 12 |
| No surface derivation | 74 |
| Neural invasion (p < 0.0001) | 47 |
| Bone invasion (p = 0.0005) | 66 |
| Lymphovascular invasion (p = 0.0058) | 33 |
| Individual, single cell invasion | 8 |
| Growth pattern | |
| Cribriform (≥70 %) | 33 |
| Tubular (≥70 %) | 16 |
| Solid (≥70 %) | 9 |
| Pleomorphism | |
| Mild | 70 |
| Moderate | 14 |
| Severe (de-differentiation) (p = 0.105) | 2 |
| Nuclear to cytoplasmic ratio | |
| Intermediate | 71 |
| High | 15 |
| Sclerosis prominent | 16 |
| Glycosaminoglycan prominent | 13 |
| Reduplicated basement membrane prominent | 52 |
| Necrosis present | 16 |
| Mitotic figures | |
| Present | 71 |
| Mean (per 10 HPF) | 7.3 |
| Range | 0–109 |
| Atypical figures (present) | 11 |
| Other features | |
| Anastomosing cords | 17 |
| Large cystic spaces | 13 |
| Pleomorphic adenoma (carcinoma ex-pleomorphic adenoma) | 9 |
| EMC-like areas | 4 |
| Squamous metaplasia | 3 |
| Dedifferentiation | 2 |
| Calcifications | 2 |
| Margin status | |
| Unknown or positive | 72 |
| Negative (p = 0.103) | 14 |
| Grade | |
| I | 22 |
| II | 37 |
| III | 27 |
HPF high power field
p Values are included to indicate features associated with a poor patient outcome when present