Clinical T

This input is used for staging


**Note 1:** Parapharyngeal involvement denotes postero-lateral infiltration of tumor beyond the pharyngobasilar fascia. The pharyngobasilar fascia is the fibrous layer of the pharyngeal wall between the mucosa and the muscular layer, attached superiorly to the basilar part of the occipital bone and diminishing in thickness as it descends. **Note 2:** The masticator space primarily consists of the muscles of mastication, the medial and lateral pterygoid, masseter, and temporalis muscles. The space also includes the ramus of the mandible and the third division of cranial nerve V as it passes through the foramen ovale into the suprahyoid neck.


Clinical T Clinical T Display Description Registrar Notes
cX cTX Primary tumor cannot be assessed Clinical classification criteria met, evaluation done:
Physician unable to assess T
Extension cannot be determined
Physician assigns cTX, no other information available to determine T
c0 cT0 No evidence of primary tumor
pIS pTis Carcinoma in situ Intraepithelial, noninvasive

Stated as Tis
c1 cT1 Tumor confined to nasopharynx, OR
extends to oropharynx and/or nasal cavity
Invasive tumor confined to one of the following subsites:
Inferior wall (superior surface of soft palate)
One lateral wall
Posterior superior wall (vault)

Involvement of two or more subsites:
Lateral wall extending into eustachian
tube/middle ear
Posterior, inferior, or lateral wall(s)

Soft palate, inferior surface including uvula
WITHOUT parapharyngeal extension

Nasal cavity WITHOUT parapharyngeal extension

Extension to soft tissue, NOS (excluding soft tissue of neck)

Confined to nasopharynx
Localized, NOS

Stated as T1
c2 cT2 Tumor with parapharyngeal extension Involvement of any T1 tumor:
WITH fixation or tumor described only as FIXED WITH parapharyngeal extension

Pterygopalatine fossa WITHOUT bone invasion

Stated as T2
c3 cT3 Tumor invades bony structures of skull base and/or paranasal sinuses Bone, NOS
Bony structures of skull base
Cartilage, NOS
Floor of orbit
Hard palate
Paranasal sinus

Stated as T3
c4 cT4 Tumor with intracranial extension and/or involvement of:
Cranial nerves

OR with extension to the infratemporal fossa/masticator space
Cranial nerve involvement
Infratemporal fossa/masticator space
Intracranial extension, NOS
Orbit except bone of floor of orbit

Further contiguous extension including:
Soft tissues of neck

Stated as T4
88 88 Not applicable Primary site/histology not TNM defined
Death certificate only (DCO) case
<BLANK> BLANK See Registrar Notes Clinical classification criteria not met
Clinical classification criteria met, evaluation done:
No information about diagnostic workup
Results not documented in record
Clinical evaluation of primary tumor not done or unknown if done
Tumor first detected on surgical resection (no clinical workup)
Evidence of metastatic disease [(cM1) or (pM1)], no other workup
Only Clinical Stage Group documented (no T, N, or M information available)