TNM Classification for Cancer of Nasal Cavity and Paranasal Sinuses

The American Joint Committee on Cancer (AJCC) tumor/node/metastasis (TNM) classifications for cancers of the nasal cavity and paranasal sinuses are provided below, along with anatomic staging.^{[1, 2]}

Table 1. TNM classification (Open Table in a new window)

Primary tumor (T)
Maxillary sinus
TX	Primary tumor cannot be assessed
Tis	Carcinoma in situ
T1	Tumor limited to maxillary sinus mucosa with no erosion or destruction of bone
T2	Tumor causing bone erosion or destruction, including extension into the hard palate and/or middle nasal meatus, except extension to posterior wall of the maxillary sinus and pterygoid plates
T3	Tumor invades any of the following: bone of the posterior wall of the maxillary sinus, subcutaneous tissues, floor or medial wall of the orbit, pterygoid fossa, ethmoid sinuses
T4	Moderately advanced or very advanced local disease
T4a	Moderately advanced local disease Tumor invades the anterior orbital contents, skin of the cheek, pterygoid plates, infratemporal fossa, cribriform plate, sphenoid or frontal sinuses
T4b	Very advanced local disease Tumor invades any of the following: orbital apex, dura, brain, middle cranial fossa, cranial nerves other than maxillary division of trigeminal nerve (V2), nasopharynx, or clivus
Nasal cavity and ethmoid sinus
TX	Primary tumor cannot be assessed
Tis	Carcinoma in situ
T1	Tumor restricted to any 1 subsite, with or without bony invasion
T2	Tumor invading 2 subsites in a single region or extending to involve an adjacent region within the nasoethmoidal complex, with or without bony invasion
T3	Tumor extends to invade the medial wall or floor of the orbit, maxillary sinus, palate, or cribriform plate
T4	Moderately advanced or very advanced local disease
T4a	Moderately advanced local disease Tumor invades any of the following: anterior orbital contents, skin of the nose or cheek, minimal extension to the anterior cranial fossa, pterygoid plates, sphenoid or frontal sinuses
T4b	Very advanced local disease Tumor invades any of the following: orbital apex, dura, brain, middle cranial fossa, cranial nerves other than maxillary division of trigeminal nerve (V2), nasopharynx, or clivus
Regional lymph nodes (N)
	Clinical N (cN)
NX	Regional lymph nodes cannot be assessed
N0	No regional lymph node metastasis
N1	Metastasis in a single ipsilateral lymph node ≤ 3 cm in greatest dimension and no extranodal extension (ENE [-])
N2	Metastasis in a single ipsilateral lymph node > 3 cm but not more than 6 cm in greatest dimension and ENE (-); or metastases in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension and ENE (-); or in bilateral or contralateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N2a	Metastasis in a single ipsilateral lymph node > 3 cm but not more than 6 cm in greatest dimension and ENE (-)
N2b	Metastasis in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N2c	Metastasis in bilateral or contralateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N3	Metastasis in a lymph node > 6 cm in greatest dimension and ENE (-); or metastasis in any node(s) with clinically overt ENE (+)
N3a	Metastasis in a lymph node > 6 cm in greatest dimension and ENE (-)
N3b	Metastasis in any node(s) with clinically overt ENE (ENE_c)
	Pathological N (pN)
Nx	Regional lymph nodes cannot be assessed
N0	No regional lymph node metastasis
N1	Metastasis in a single ipsilateral lymph node ≤ 3 cm in greatest dimension and ENE (-)
N2	Metastasis in a single ipsilateral lymph node, 3 cm or smaller in greatest dimension and ENE (+); or > 3 cm but not more than 6 cm in greatest dimension and ENE (-); or metastases in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension and ENE (-); or in bilateral or contralateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N2a	Metastasis in a single ipsilateral lymph node, 3 cm or smaller in greatest dimension and ENE (+); or a single ipsilateral node > 3 cm but not more than 6 cm in greatest dimension and ENE (-);
N2b	Metastasis in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N2c	Metastasis in bilateral or contralateral lymph node(s), none > 6 cm in greatest dimension and ENE (-)
N3	Metastasis in a lymph node > 6 cm in greatest dimension and ENE (-); or in a single ipsilateral node > 3 cm in greatest dimension and ENE (+); or multiple ipsilateral, contralateral, or bilateral nodes, any with ENE (+); or a single contralateral node of any size and ENE (+)
N3a	Metastasis in a lymph node > 6 cm in greatest dimension and ENE (-)
N3b	Metastasis in a single ipsilateral node > 3 cm in greatest dimension and ENE (+); or multiple ipsilateral, contralateral, or bilateral nodes, any with ENE (+); or a single contralateral node of any size and ENE (+)
Distant metastasis (M)
cM0	No distant metastasis
cM1	Distant metastasis
pM1	Distant metastasis, microscopically confirmed

Table 2. Histologic grade (Open Table in a new window)

Histologic grade (G)
GX	Grade cannot be assessed
G1	Well differentiated
G2	Moderately differentiated
G3	Poorly differentiated

Table 3. Anatomic stage/prognostic groups (Open Table in a new window)

Stage	T	N	M
0	Tis	N0	M0
I	T1	N0	M0
II	T2	N0	M0
III	T3	N0	M0
	T1	N1	M0
	T2	N1	M0
	T3	N1	M0
IVA	T4a	N0	M0
	T4a	N1	M0
	T1	N2	M0
	T2	N2	M0
	T3	N2	M0
	T4a	N2	M0
IVB	T Any	N3	M0
IVB	T4b	N Any	M0
IVC	T Any	N Any	M1

Media Gallery

of 0

Table 1. TNM classification

Primary tumor (T)
Maxillary sinus
TX	Primary tumor cannot be assessed
Tis	Carcinoma in situ
T1	Tumor limited to maxillary sinus mucosa with no erosion or destruction of bone
T2	Tumor causing bone erosion or destruction, including extension into the hard palate and/or middle nasal meatus, except extension to posterior wall of the maxillary sinus and pterygoid plates
T3	Tumor invades any of the following: bone of the posterior wall of the maxillary sinus, subcutaneous tissues, floor or medial wall of the orbit, pterygoid fossa, ethmoid sinuses
T4	Moderately advanced or very advanced local disease
T4a	Moderately advanced local disease Tumor invades the anterior orbital contents, skin of the cheek, pterygoid plates, infratemporal fossa, cribriform plate, sphenoid or frontal sinuses
T4b	Very advanced local disease Tumor invades any of the following: orbital apex, dura, brain, middle cranial fossa, cranial nerves other than maxillary division of trigeminal nerve (V2), nasopharynx, or clivus
Nasal cavity and ethmoid sinus
TX	Primary tumor cannot be assessed
Tis	Carcinoma in situ
T1	Tumor restricted to any 1 subsite, with or without bony invasion
T2	Tumor invading 2 subsites in a single region or extending to involve an adjacent region within the nasoethmoidal complex, with or without bony invasion
T3	Tumor extends to invade the medial wall or floor of the orbit, maxillary sinus, palate, or cribriform plate
T4	Moderately advanced or very advanced local disease
T4a	Moderately advanced local disease Tumor invades any of the following: anterior orbital contents, skin of the nose or cheek, minimal extension to the anterior cranial fossa, pterygoid plates, sphenoid or frontal sinuses
T4b	Very advanced local disease Tumor invades any of the following: orbital apex, dura, brain, middle cranial fossa, cranial nerves other than maxillary division of trigeminal nerve (V2), nasopharynx, or clivus
Regional lymph nodes (N)
	Clinical N (cN)
NX	Regional lymph nodes cannot be assessed
N0	No regional lymph node metastasis
N1	Metastasis in a single ipsilateral lymph node ≤ 3 cm in greatest dimension and no extranodal extension (ENE [-])
N2	Metastasis in a single ipsilateral lymph node > 3 cm but not more than 6 cm in greatest dimension and ENE (-); or metastases in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension and ENE (-); or in bilateral or contralateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N2a	Metastasis in a single ipsilateral lymph node > 3 cm but not more than 6 cm in greatest dimension and ENE (-)
N2b	Metastasis in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N2c	Metastasis in bilateral or contralateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N3	Metastasis in a lymph node > 6 cm in greatest dimension and ENE (-); or metastasis in any node(s) with clinically overt ENE (+)
N3a	Metastasis in a lymph node > 6 cm in greatest dimension and ENE (-)
N3b	Metastasis in any node(s) with clinically overt ENE (ENE_c)
	Pathological N (pN)
Nx	Regional lymph nodes cannot be assessed
N0	No regional lymph node metastasis
N1	Metastasis in a single ipsilateral lymph node ≤ 3 cm in greatest dimension and ENE (-)
N2	Metastasis in a single ipsilateral lymph node, 3 cm or smaller in greatest dimension and ENE (+); or > 3 cm but not more than 6 cm in greatest dimension and ENE (-); or metastases in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension and ENE (-); or in bilateral or contralateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N2a	Metastasis in a single ipsilateral lymph node, 3 cm or smaller in greatest dimension and ENE (+); or a single ipsilateral node > 3 cm but not more than 6 cm in greatest dimension and ENE (-);
N2b	Metastasis in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension and ENE (-)
N2c	Metastasis in bilateral or contralateral lymph node(s), none > 6 cm in greatest dimension and ENE (-)
N3	Metastasis in a lymph node > 6 cm in greatest dimension and ENE (-); or in a single ipsilateral node > 3 cm in greatest dimension and ENE (+); or multiple ipsilateral, contralateral, or bilateral nodes, any with ENE (+); or a single contralateral node of any size and ENE (+)
N3a	Metastasis in a lymph node > 6 cm in greatest dimension and ENE (-)
N3b	Metastasis in a single ipsilateral node > 3 cm in greatest dimension and ENE (+); or multiple ipsilateral, contralateral, or bilateral nodes, any with ENE (+); or a single contralateral node of any size and ENE (+)
Distant metastasis (M)
cM0	No distant metastasis
cM1	Distant metastasis
pM1	Distant metastasis, microscopically confirmed