CS Extension

Notes

**Note 1**: The intrinsic muscles of tongue are four paired muscles within the tongue which control its shape. The extrinsic muscles originate from structures outside the tongue and control its positioning. **Note 2**: 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, 650, 775, 810, or 815 as appropriate to code CS Extension based on a statement of T when no other extension information is available. **Note 3**: Use code 300 for localized tumor only if no information is available to assign codes 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 posterior one-third of tongue: Lamina propria Submucosa	Extension Size AJCC7	Extension Size AJCC6	L	L
200	Musculature, intrinsic or NOS	Extension Size AJCC7	Extension Size AJCC6	L	L
300	Localized, NOS Midline tumor	Extension Size AJCC7	Extension Size AJCC6	L	L
400	Base of tongue tumor crosses midline Tumor of lingual tonsil on both sides	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	Anterior two-thirds of tongue for base of tongue Lingual tonsil for base of tongue Base of tongue for lingual tonsil Floor of mouth Lower gingiva	Extension Size AJCC7	Extension Size AJCC6	RE	RE
530	Sublingual gland	Extension Size AJCC7	Extension Size AJCC6	RE	RE
600	OBSOLETE DATA RETAINED V0200 Epiglottis, lingual surface assigned to T3 in AJCC 7, see code 640 Epiglottis, lingual (pharyngeal) surface Glossoepiglottic fold Glossopharyngeal fold Lateral pharyngeal wall Pharyngoepiglottic fold Tonsillar pillars and fossae Tonsils Vallecula	ERROR:	Extension Size AJCC6	RE	RE
610	Glossoepiglottic fold Glossopharyngeal fold Lateral pharyngeal wall Pharyngoepiglottic fold Tonsillar pillars and fossae Tonsils Vallecula	Extension Size AJCC7	Extension Size AJCC6	RE	RE
620	Soft palate, inferior surface or NOS including uvula	Extension Size AJCC7	Extension Size AJCC6	D	RE
640	Epiglottis, lingual surface	T3	Extension Size AJCC6	RE	RE
645	640 + 620 Epiglottis, lingual surface plus soft palate	T3	Extension Size AJCC6	D	RE
650	Stated as T3 with no other information on extension	T3	Extension Size AJCC6	RE	RE
710	Mandible for lingual tonsil	T4a	T4a	RE	D
715	710 + 620 Mandible plus soft palate	T4a	T4a	D	D
720	Mandible for base of tongue	T4a	T4a	D	D
740	Medial pterygoid muscle Hard palate	T4a	T4a	D	D
750	Musculature of tongue, extrinsic: Genioglossus Geniohyoid Hyoglossus Mylohyoid Palatoglossus Styloglossus	T4a	T4a	D	D
760	Hypopharynx	T4a	T4a	D	D
770	Larynx	T4a	T4a	D	D
775	Stated as T4a with no other information on extension	T4a	T4a	RE	RE
780	Skin	T4b	T4b	D	D
790	Lateral nasopharynx Lateral pterygoid muscle Pterygoid plates	T4b	T4b	D	D
795	(770, 780, or 790) + 760	T4b	T4b	D	D
800	OBSOLETE DATA REVIEWED AND CHANGED V0203 Recode involved structures to 620, 645, 715, 760, 790, or 795 as appropriate. Contiguous extension to: Base of skull Carotid artery Hypopharynx Lateral nasopharynx Lateral pterygoid muscle Pterygoid plates Uvula	ERROR:	ERROR:	ERROR:	ERROR:
805	Further contiguous extension including: Skull base Carotid artery (encased)	T4b	T4b	D	D
810	Stated as T4b with no other information on extension	T4b	T4b	D	D
815	Stated as T4 [NOS] with no other information on extension	T4NOS	T4NOS	RE	RE
820	OBSOLETE DATA CONVERTED V0200 See code 805 Further contiguous extension	ERROR:	ERROR:	ERROR:	ERROR:
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 CS Extension codes 100-620 ONLY, the T category for AJCC 7 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 100-650 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.