Primary tumor (T) |
T category | T criteria |
TX | Primary tumor cannot be assessed (eg, curetted) |
T0 | No evidence of primary tumor |
Tis | In situ primary tumor |
T1 | Maximum clinical tumor diameter ≤2 cm |
T2 | Maximum clinical tumor diameter >2 but ≤5 cm |
T3 | Maximum clinical tumor diameter >5 cm |
T4 | Primary tumor invades fascia, muscle, cartilage, or bone |
Regional lymph nodes (N) |
Pathological (pN) |
pN category | pN criteria |
pNX | Regional lymph nodes cannot be assessed (eg, previously removed for another reason or not removed for pathological evaluation) |
pN0 | No regional lymph node metastasis detected on pathological evaluation |
pN1 | Metastasis in regional lymph node(s) |
pN1a(sn) | Clinically occult regional lymph node metastasis identified only by sentinel lymph node biopsy |
pN1a | Clinically occult regional lymph node metastasis following lymph node dissection |
pN1b | Clinically and/or radiologically detected regional lymph node metastasis, microscopically confirmed |
pN2 | In-transit metastasis (discontinuous from primary tumor; located between primary tumor and draining regional nodal basin, or distal to the primary tumor) without lymph node metastasis |
pN3 | In-transit metastasis (discontinuous from primary tumor; located between primary tumor and draining regional nodal basin, or distal to the primary tumor) with lymph node metastasis |
Distant metastasis (M) |
Pathological (M) |
M category | M criteria |
M0 | No distant metastasis detected on clinical and/or radiologic examination |
pM1 | Distant metastasis microscopically confirmed |
pM1a | Metastasis to distant skin, distant subcutaneous tissue, or distant lymph node(s), microscopically confirmed |
pM1b | Metastasis to lung, microscopically confirmed |
pM1c | Metastasis to all other distant sites, microscopically confirmed |
Prognostic stage groups |
Pathological stage group (pTNM) |
When T is... | And N is... | And M is... | Then the stage group is... |
Tis | N0 | M0 | 0 |
T1 | N0 | M0 | I |
T2-3 | N0 | M0 | IIA |
T4 | N0 | M0 | IIB |
T1-4 | N1a(sn) or N1a | M0 | IIIA |
T0 | N1b | M0 | IIIA |
T1-4 | N1b-3 | M0 | IIIB |
T0-4 | Any N | M1 | IV |