Part of Cancer staging guidance sheets
Oral Cavity and mucosal lip (ICD10 C00.3-5, C02-C06)
Introduction
This is the data sheet for TNM 9th edition staging of the oral cavity and mucosal lip (ICD10 C00.3-5, C02-C06).
For more detailed information regarding TNM staging, please see pages 18-22 of the UICC TNM 9 book.
Stage groupings
|
Stage Group |
T stage |
N stage |
M stage |
|---|---|---|---|
|
Stage 0 |
Tis |
N0 |
M0 |
|
Stage I |
T1 |
N0 |
M0 |
|
Stage II |
T2 |
N0 |
M0 |
|
Stage III |
T3 |
N0 |
M0 |
|
T1, T2, T3 |
N1 |
M0 |
|
|
Stage IVA |
T4a |
N0, N1 |
M0 |
|
T1, T2, T3, T4a |
N2 |
M0 |
|
|
Stage IVB |
Any T |
N3 |
M0 |
|
T4b |
Any N |
M0 |
|
|
Stage IVC |
Any T |
Any N |
M1 |
TNM clinical classification
T - primary tumour
|
T value |
Description |
|---|---|
|
cTX |
Primary tumour cannot be assessed |
|
cT0 |
No evidence of primary tumour |
|
cTis |
Carcinoma in situ |
|
cT1 |
Tumour 2 cm or less in greatest dimension and 5mm or less depth of invasion1,2 |
|
cT2 |
Tumour 2 cm or less in greatest dimension and more than 5mm depth of invasion or, Tumour more than 2 cm but not more than 4 cm in greatest dimension and depth of invasion no more than 10mm |
|
cT3 |
Tumour more than 2 cm but not more than 4 cm in greatest dimension and depth of invasion more than 10 mm or |
|
|
Tumour more than 4 cm in greatest dimension and not more than 10 mm depth of invasion |
|
cT4a |
Tumour more than 4cm in greatest dimension and more than 10 mm depth of invasion or |
|
|
Tumour invades through the cortical bone (with involvement of spongiosa/spongy bone) of the mandible or maxilla or involves the maxillary sinus, or invades the skin of the face2 |
|
cT4b |
Tumour invades masticator space, pterygoid plates, or skull base, or encases internal carotid artery |
Note:
1Superficial erosion alone of bone/tooth socket by gingival primary is not sufficient to classify a tumour as cT4a
2Superficial invasion of adjacent skin (i.e, dry vermillion border of the lip) from mucosal lip is not sufficient to be classified as a T4a tumour
N - regional lymph nodes
|
N value |
Description |
|---|---|
|
cNX |
Regional lymph nodes cannot be assessed |
|
cN0 |
No regional lymph node metastasis |
|
cN1 |
Metastasis in a single ipsilateral lymph node, 3 cm or less in greatest dimension without extranodal extension |
|
cN2 |
Metastasis described as: cN2a - Metastasis in a single ipsilateral lymph node, more than 3 cm but not more than 6 cm in greatest dimension without extranodal extension |
|
|
cN2b - Metasis in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension without extranodal extension |
|
|
cN2c - Metastasis in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension without extranodal extension |
|
cN3a |
Metastasis in a lymph node more than 6 cm in greatest dimension without extranodal extension |
|
cN3b |
Metastasis in a single or multiple lymph node with clinical extranodal extension* |
Notes:
*Clinical extranodal extension is defined as the presence of skin involvement or soft tissue invasion with deep fixation to underlying muscle or adjacent anatomical structures or clinical signs of nerve involvement. Imaging is becoming a standard method of detecting unequivocal extranodal extension.
Midline nodes are considered ipsilateral nodes
M - distant metastasis
|
M value |
Description |
|---|---|
|
cM0 |
No distant metastasis |
|
cM1 |
Distant Metastasis |
TNM pathological classification
pT - primary tumour
The pT categories correspond to the T categories.
pN - regional lymph nodes
Histological examination of a selective neck dissection specimen will ordinarily include 10 or more lymph nodes. Histological examination of a radical or modified radical neck dissection specimen will ordinarily include 15 or more lymph nodes.
|
pN value |
Description |
|---|---|
|
pNX |
Regional lymph nodes cannot be assessed |
|
pN0 |
No regional lymph node metastasis |
|
pN1 |
Metastasis in a single ipsilateral lymph node, 3 cm or less in greatest dimension without extranodal extension |
|
pN2 |
pN2a - Metastasis in a single ipsilateral lymph node, 3cm or less in greatest dimension with extranodal extension or more than 3 cm but not more than 6 cm in greatest dimension without extranodal extension |
|
|
pN2b - Metastasis in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension, without extranodal extension |
|
|
pN2c - Metastasis in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension without extranodal extension |
|
pN3a |
Metastasis in a lymph node more than 6 cm in greatest dimension without pathological extranodal extension |
|
pN3b |
Metastasis in a single lymph node more than 3cm in greatest dimension with pathological extranodal extension* OR metastasis in multiple ipsilateral, or any contralateral or bilateral node(s) with pathological extranodal extension* |
Note:
*Pathological extranodal extension (pENE) should only be diagnosed when tumour that is present within the confines of a lymph node definitively transgresses through the entire thickness of the lymph node capsule into the surrounding connective tissue, with or without stromal reaction. A soft tissue deposit should be considered as at least one lymph node with extranodal extension if it occurs at a site where a regional lymph node would be expected.
Last edited: 16 January 2026 3:47 pm
