Table 1.
TNM classifications | |||
Primary tumor (T) | |||
TX | Primary tumor cannot be assessed | ||
Tis | Carcinoma in situ (noninvasive cancer) | ||
T1 | Tumor invades mucosa (T1a) or submucosa (T1b) | ||
T2 | Tumor invades muscularis propria | ||
T3 | Tumor invades adventitia | ||
T4 | Tumor invades adjacent structures | ||
Regional lymph nodes (N) | |||
NX | Regional lymph nodes cannot be assessed | ||
N0 | No regional lymph node metastasis | ||
N1 | Regional lymph node metastasis (cancer-positive lymph nodes) | ||
Distant metastasis (M) | |||
MX | Distant metastasis cannot be assessed | ||
M0 | No distant metastasis | ||
M1 | Distant metastasis (M1a†, M1b‡) | ||
NonTNM cancer characteristics | |||
Histopathologic type | Squamous cell carcinoma, adenocarcinoma | ||
Histologic grade (G) | |||
GX | Grade cannot be assessed | ||
G1 | Well differentiated | ||
G2 | Moderately differentiated | ||
G3 | Poorly differentiated | ||
G4 | Undifferentiated | ||
Stage groupings | |||
0 | Tis | N0 | M0 |
I | T1 | N0 | M0 |
IIA | T2–3 | N0 | M0 |
IIB | T1–2 | N1 | M0 |
III | T3 | N1 | M0 |
T4 | Any N | M0 | |
IV | Any T | Any N | M1 |
IVA | Any T | Any N | M1a |
IVB | Any T | Any N | M1b |
M1a = metastases to select nonregional lymph nodes.
M1b = other distant metastases.