CS Extension

Notes

**Note 1**: The assignment of T1 and T2 categories for tumors of the oropharynx is based on tumor size. A physician's statement of the T category may be used to code CS Tumor Size and/or CS Extension if this is the only information in the medical record regarding one or both of these fields. However the two fields are coded independently: for example the record may document size but not extension, other than the physician's statement of the T category. Use codes 405, 410, 645, 735, 810, or 815 as appropriate to code CS Extension based on a statement of T when no other extension information is available. **Note 2**: Use code 300 for localized tumor ONLY if no information is available to assign code 100, 200, 400, 405, or 410.
Code Description AJCC 7 T AJCC 6 T Summary Stage 1977 T Summary Stage 2000 T
000 In situ, intraepithelial, noninvasive Tis Tis IS IS
100 Invasive tumor on one side confined to:
Lamina propria
Submucosa		 Extension Size AJCC7 Extension Size AJCC6 L L
200 Musculature invaded Extension Size AJCC7 Extension Size AJCC6 L L
300 Localized, NOS Extension Size AJCC7 Extension Size AJCC6 L L
400 Tumor crosses midline Extension Size AJCC7 Extension Size AJCC6 L L
405 Stated as T1 with no other information on extension Extension Size AJCC7 Extension Size AJCC6 L L
410 Stated as T2 with no other information on extension Extension Size AJCC7 Extension Size AJCC6 L L
500 Buccal mucosa (inner cheek)
Gum (gingiva), upper		 Extension Size AJCC7 Extension Size AJCC6 RE RE
600 Lateral pharyngeal wall
Tonsillar pillars and fossae
Tonsils		 Extension Size AJCC7 Extension Size AJCC6 RE RE
640 Epiglottis, lingual surface T3 Extension Size AJCC6 D D
645 Stated as T3 with no other information on extension T3 Extension Size AJCC6 RE RE
650 Hard palate T4a T4a RE RE
670 Nasal cavity T4a T4a RE D
675 (650 or 670) + 640

Hard palate or nasal cavity plus epiglottis, lingual surface		 T4a T4a D D
700 Mandible
Maxilla
Palatine bone (bone of hard palate)		 T4a T4a D D
710 Pterygoid muscle, medial or NOS T4a T4a D D
720 Tongue
Deep (extrinsic) muscle of tongue:
Genioglossus
Geniohyoid
Hyoglossus
Mylohyoid
Palatoglossus
Styloglossus		 T4a T4a D D
730 Larynx
Hypopharynx		 T4a T4a D D
733 (700, 710, 720, or 730) + 670 T4a T4a D D
735 Stated as T4a with no other information on extension T4a T4a RE RE
740 Maxillary sinus (antrum)
Nasopharynx, lateral or NOS		 T4b T4b D D
745 740 + 670 T4b T4b D D
770 OBSOLETE DATA CONVERTED V0200
See code 670

Nasal cavity		 ERROR: ERROR: ERROR: ERROR:
780 Pterygoid muscle, lateral
Pterygoid plates

Note: For medial pterygoid muscle or pterygoid muscle, NOS, see code 710		 T4b T4b RE D
790 780 + (640, 700 - 730, or 740)

Any structure in 780 plus any structure in 640, 700 - 730, or 740		 T4b T4b D D
800 Further contiguous extension including:
Carotid artery (encased)
Skull base		 T4b T4b D D
810 Stated as T4b with no other information on extension T4b T4b RE D
815 Stated as T4 [NOS] with no other information on extension T4NOS T4NOS RE RE
950 No evidence of primary tumor T0 T0 U U
999 Unknown; extension not stated
Primary tumor cannot be assessed
Not documented in patient record		 TX TX U U
- For CSExtension codes 100-600 ONLY, the T category for AJCC staging is assigned based on the value of CS Tumor Size, as shown in the Extension Size AJCC 7 Table for this schema. - For CS Extension codes 100-645 ONLY, the T category for AJCC 6 staging is assigned based on the value of CS Tumor Size, as shown in the Extension Size AJCC 6 Table for this schema.