TNM Classification for Nasopharyngeal Cancers
The American Joint Committee on Cancer (AJCC) tumor/node/metastasis (TNM) classifications and prognostic stage groups for nasopharyngeal cancers are provided below. [1]
Table 1. TNM classification (Open Table in a new window)
Primary tumor (T) |
|
TX |
Primary tumor cannot be assessed |
T0 |
No tumor ifentified, but EBV-positive cervical node(s) involvement |
Tis |
Carcinoma in situ |
T1 |
Tumor confined to the nasopharynx, or extenion to oropharynx and/or nasal cavity without parapharyngeal involvement |
T2 |
Tumor with extension to parapharyngeal space, and/or adjacent soft tissue involvement (medial pterygoid, lateral pterygoid, prevertebral muscles) |
T3 |
Tumor with infiltration of bony structures at skull base, cervical vertebra, pterygoid structures, and/or paranasal sinuses |
T4 |
Tumor with intracranial extension, involvement of cranial nerves, hypopharynx, orbit, parotid gland, and/or extensive soft tissue infiltration beyond the lateral surface of the lateral pterygoid muscle |
Regional lymph nodes (N) |
|
NX |
Regional nodes cannot be assessed |
N0 |
No regional lymph node metastasis |
N1 |
Unilateral metastasis in cervical lymph node(s) and/or unilateral or bilateral metastasis in retropharyngeal lymph node(s), 6 cm or smaller in greatest dimension, above the caudal border of cricoid cartilage |
N2 |
Bilateral metastasis in cervical lymph node(s), 6 cm or smaller in greatest dimension, above the caudal border of cricoid cartilage |
N3 |
Unilateral or bilateral metastasis in cervical lymph node(s), larger than 6 cm in greatest dimension, and/or extension below the caudal border of cricoid cartilage |
Distant metastasis (M) |
|
cM0 |
No distant metastasis |
cM1 |
Distant metastasis |
pM1 | Distant metastasis, microscopically confirmed |
Table 2. Prognostic stage groups (Open Table in a new window)
Stage |
T |
N |
M |
0 |
Tis |
N0 |
M0 |
I |
T1 |
N0 |
M0 |
II |
T0–T1 |
N1 |
M0 |
T2 |
N0–N1 |
M0 |
|
III |
T0–T3 |
N2 |
M0 |
T3 |
N1–N2 |
M0 |
|
IVA
|
T4 |
N0–N2 |
M0 |
T Any |
N3 |
M0 |
|
IVB |
T Any |
N Any |
M1 |