CS Extension
Notes
**Note 1**: AJCC does not include a Tis or TX 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 320 and 325 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 100, 350, or 360. **Note 5**: Use code 350, 725, 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 | Tumor confined to mucosa of maxillary antrum (sinus) | T3 | NA | L | L |
| 300 | Localized, NOS | T3 | NA | L | L |
| 320 | Extension involving mucosa only: Frontal sinus Sphenoid sinus Ethmoid sinus |
T3 | NA | RE | RE |
| 325 | Extension involving mucosa only: Nasal cavity Nasopharynx |
T3 | NA | RE | RE |
| 350 | Stated as T3 with no other information on extension | T3 | NA | L | L |
| 360 | Involvement of deep tissue or mucoperiosteum of maxillary sinus | T4a | NA | L | L |
| 365 | 360 + (320 or 325) Involvement of deep tissue or mucoperiosteum of maxillary sinus plus mucosal involvement of any structure in code 320 or 325 |
T4a | NA | RE | RE |
| 400 | OBSOLETE DATA RETAINED V0200 Invasion of infrastructure: Hard palate except extension to posterior wall of sinus and pterygoid plates (code 680) Middle nasal meatus, except extension to posterior wall of sinus and pterygoid plates (code 680) Nasal cavity (floor, lateral wall, septum, turbinates) Palatine bone Tumor causing bone erosion or destruction, except for the posterior antral wall |
ERROR: | NA | RE | RE |
| 500 | Involvement of deep tissues, mucoperiosteum, cartilage, or bony wall of any structures in code 320 | T4a | NA | RE | RE |
| 510 | Involvement of deep soft tissues, cartilage, or bony wall of any structures in code 325 | T4a | NA | RE | RE |
| 520 | Involvement of palatine bone | T4a | NA | RE | RE |
| 600 | OBSOLETE DATA RETAINED V0200 Invasion of suprastructure: Ethmoid sinus, anterior Floor or medial wall of orbit Floor or posterior wall of maxillary sinus Subcutaneous tissues |
ERROR: | NA | RE | RE |
| 650 | OBSOLETE DATA RETAINED V0200 Bone of the posterior wall of maxillary sinus Invasion of maxilla, NOS |
ERROR: | NA | RE | RE |
| 660 | OBSOLETE DATA RETAINED V0200 Ethmoid sinus Posterior ethmoid, NOS Pterygoid sinus |
ERROR: | NA | RE | RE |
| 670 | Infratemporal fossa Pterygoid plates Pterygoid fossa |
T4a | NA | RE | RE |
| 675 | Subcutaneous tissues Skin of cheek Skin of nose |
T4a | NA | RE | RE |
| 680 | OBSOLETE DATA RETAINED V0200 Anterior orbital contents Cribriform plate Frontal sinus Infratemporal fossa Pterygoid plates Skin of cheek Sphenoid sinus |
ERROR: | NA | RE | RE |
| 690 | Orbital contents including eye Soft palate |
T4a | NA | RE | RE |
| 700 | OBSOLETE DATA RETAINED V0200 Base of skull Orbital contents, including eye Pterygomaxillary (temporal) fossa Soft palate |
ERROR: | NA | RE | RE |
| 725 | Stated as T4a with no other information on extension | T4a | NA | L | L |
| 740 | Anterior cranial fossa Base of skull Clivus Cribriform plate Middle cranial fossa Orbital apex Pterygomaxillary (temporal) fossa |
T4b | NA | RE | RE |
| 750 | OBSOLETE DATA RETAINED V0200 Brain Clivus Cranial nerves other than (V2) Dura Middle cranial fossa Nasopharynx Orbital apex |
ERROR: | NA | U | U |
| 790 | Contiguous extension to: Dura Brain Lower cranial nerves (IX, X, XI, XII) Middle cranial fossa |
T4b | NA | RE | RE |
| 800 | OBSOLETE DATA RETAINED V0200 Further contiguous extension |
ERROR: | NA | D | D |
| 801 | Further contiguous extension : Carotid artery (encased) Masticator space Mediastinal structures Prevertebral 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 |