CS Extension

Notes

**Note 1**: AJCC does not include a Tis or TX category for melanoma of mucosa of head and neck sites. CS Extension codes of 000 and 999 are mapped to NA and AJCC stage group is derived as NA. **Note 2**: AJCC does not include a T1 or T2 category for mucosal melanoma of head and neck sites. **Note 3**: Use codes 205 and 310 for extension involving the mucosa only of adjacent sites. Use higher codes for extension involving the deeper tissues of the primary or adjacent sites. **Note 4**: Use code 300 for localized tumor only if no information is available to assign code 105, 205, or 320. **Note 5**: Use code 320, 638, 810, or 815 if the physician's assignment of T category is the only information available about the extent of the tumor.
Code Description AJCC 7 T AJCC 6 T Summary Stage 1977 T Summary Stage 2000 T
000 In situ, intraepithelial, noninvasive NA NA IS IS
100 OBSOLETE DATA RETAINED V0200

Invasive tumor confined to one of the following subsites:
Laryngopharynx
Postcricoid area
Posterior pharyngeal wall
Pyriform sinus
ERROR: NA L L
105 Tumor confined to mucosa of one of the following subsites:
Laryngopharynx
Postcricoid area
Posterior pharyngeal wall
Pyriform sinus
T3 NA L L
150 OBSOLETE DATA CONVERTED V0200
See code 420

Code 100 with tumor fixation
ERROR: ERROR: ERROR: ERROR:
200 OBSOLETE DATA RETAINED V0200

Tumor invades more than one subsite of hypopharynx (listed in code 100) WITHOUT fixation
ERROR: NA L L
205 Tumor involves mucosa of more than one subsite of hypopharynx (listed in code 105)
WITHOUT fixation
T3 NA L L
300 Localized, NOS T3 NA L L
310 Involvement of mucosa only:
Larynx
Nasopharynx
Oropharynx
T3 NA RE RE
320 Stated as T3 with no other information on extension T3 NA L L
400 OBSOLETE DATA RETAINED V0200

Oropharynx
ERROR: NA RE RE
410 Involvement of deep soft tissue or musculature of any structure in code 105 or 205
Soft tissue, NOS
T4a NA L L
415 410 + 310

Involvement of deep soft tissue or musculature of any structure in code 105 or 205 plus mucosal involvement of any structure in code 310
T4a NA RE RE
420 Involvement of any structure in code 105 or 205
WITH tumor fixation
T4a NA RE RE
430 Involvement of deep soft tissue or musculature of any structure in code 310 T4a NA RE RE
450 OBSOLETE DATA RETAINED V0200

Code 200, 300, or 400 with tumor fixation
ERROR: NA RE RE
500 OBSOLETE DATA RETAINED V0200

Larynx
ERROR: NA RE RE
510 OBSOLETE DATA CONVERTED V0104
See code 450

Any of codes 100-400 WITH fixation of tumor or fixation, NOS
ERROR: ERROR: ERROR: ERROR:
550 Fixation of hemilarynx or larynx T4a NA RE RE
600 Central compartment soft tissues of neck including:
Prelaryngeal strap muscles
Subcutaneous fat
T4a NA D D
610 Esophagus T4a NA RE RE
620 Thyroid gland T4a NA D RE
630 Cricoid cartilage
Thyroid cartilage
Cartilage, NOS
T4a NA D RE
635 Hyoid bone
Bone excluding base of skull
Bone, NOS
Overlying skin
T4a NA D D
638 Stated as T4a with no other information on extension T4a NA L L
640 Prevertebral fascia/muscle(s) T4b NA RE RE
645 640 + 635

Prevertebral fascia/muscles plus any structure in code 635
T4b NA D D
650 Carotid artery (encased) T4b NA D RE
655 650 + 635

Carotid artery plus any structure in code 635
T4b NA D D
660 OBSOLETE DATA CONVERTED V0200
See code 635

Hyoid bone
ERROR: ERROR: ERROR: ERROR:
700 Mediastinal structures T4b NA D D
800 OBSOLETE DATA RETAINED V0200

Further contiguous extension
ERROR: NA D D
801 Further contiguous extension including:
Base of skull
Brain
Dura
Lower cranial nerves (IX, X, XI, XII)
Masticator space
T4b NA D D
810 Stated as T4b with no other information on extension T4b NA D D
815 Stated as T4 [NOS] with no other information on extension T4NOS NA L L
950 OBSOLETE DATA RETAINED V0200

No evidence of primary tumor
ERROR: NA U U
999 Unknown; extension not stated
Primary tumor cannot be assessed
Not documented in patient record
NA NA U U