Pathologic Staging of Non-HPV–Associated Oropharyngeal Cancer*

I

T1

pN0

M0

II

T2

pN0

M0

III

T3

pN0

M0

T1-3

pN1

M0

IVA

T4a

pN0-1

M0

T1-4a

pN2

M0

IVB

T4b

Any pN

M0

Any T

pN3

M0

IVC

Any T

Any pN

M1

* HPV association as indicated by p16 positivity.

† Definition of Primary Tumor (T) in Oropharynx (p16-)

Tis

Carcinoma in situ

T1

Tumor ≤ 2 cm in greatest dimension

T2

Tumor > 2 cm but ≤ 4 cm

T3

Tumor > 4 cm OR extension to lingual surface of epiglottis

T4a

Moderately advanced local disease; tumor invades the larynx, extrinsic tongue muscles, medial pterygoid, hard palate, or mandible (Note: mucosal extension to lingual surface of epiglottis from primary tumors of the base of the tongue and vallecula does not constitute invasion of the larynx)

T4b

Very advanced local disease; tumor invades lateral pterygoid muscle, pterygoid plates, lateral nasopharynx, or skull base or encases carotid artery

† Definition of Primary Tumor (T) in Hypopharynx

Tis

Carcinoma in situ

T1

Tumor limited to one subsite of hypopharynx and/or ≤ 2 cm

T2

Tumor invades more than one subsite of hypopharynx or an adjacent site, OR is > 2 cm but ≤ 4 cm without fixation of hemilarynx

T3

Tumor > 4 cm OR with fixation of hemilarynx or extension to esophagus

T4a

Moderately advanced local disease; tumor invades thyroid/cricoid cartilage, hyoid bone, thyroid gland, or central compartment soft tissue (including prelaryngeal strap muscles and subcutaneous fat)

T4b

Very advanced local disease; tumor invades prevertebral fascia, encases carotid artery, or involves mediastinal structures

‡ Definition of Pathologic N (pN) — Oropharynx (p16-) and Hypopharynx

N0

No regional lymph node metastasis

N1

Metastasis to one ipsilateral lymph node, ≤ 3 cm, no extranodal extension

N2

Metastasis in one ipsilateral node ≤ 3 cm with extranodal extension OR > 3 cm but ≤ 6 cm and no extranodal extension; OR in multiple ipsilateral nodes, < 6 cm and no extranodal extension; OR in bilateral or contralateral lymph nodes ≤ 6 cm and no extranodal extension

N3

Metastasis in a lymph node > 6 cm and no extranodal extension; OR in one ipsilateral node > 3 cm with extranodal extension; OR in multiple ipsilateral, contralateral, or bilateral nodes, any with extranodal extension

§ Definition of Distant Metastasis (M) — Oropharynx (p16-) and Hypopharynx

M0

No distant metastasis

M1

Distant metastasis