Tumor histopathologic grade and TNM stagea
| Tumor Characteristics | No. of Patients (%) |
|---|---|
| Hyams grade | |
| I | 3 (12) |
| II | 17 (65) |
| III | 6 (23) |
| IV | 0 (0) |
| Tumor stage | |
| Primary tumor | |
| T1 | 21 (49) |
| T2 | 10 (23) |
| T3 | 4 (9) |
| T4 | 8 (19) |
| Lymph nodes | |
| N0 | 38 (88) |
| N1 | 1 (2) |
| N2B | 1 (2) |
| N2C | 3 (7) |
| Distant metastasis | |
| M0 | 42 (98) |
| M1 | 1 (2) |
a Of the 26 patients with pathology-reported Hyams grade, 77% had low-grade ENB (grade I or II). Tumor was found to have spread beyond in the nasal cavity and paranasal sinuses in 51% of patients, most frequently invading the cribriform plate (23%). Five patients (11%) were found to have cervical metastasis at initial staging.