CS Extension

Notes

**Note 1**: For this schema, AJCC defines Tis as carcinoma in situ/dysplasia (tumor size less than 0.5mm), confined to mucosa. Neuroendocrine tumors (NET) stated to be in situ, noninvasive, or confined to mucosa are classified as Tis. "Dysplasia" alone is generally not reportable in cancer registries but, if a registry does collect it, code 000 should be used. **Note 2**: Intraluminal or intramural extension to esophagus and duodenum is classified by the depth of greatest invasion. For extension to esophagus or duodenum via serosa, see code 600. **Note 3**: The assignment of the T1 category for NETs of the stomach is based on tumor size. A physician's statement of the T category may be used to code both 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. Use codes 170, 390, 480, or 810 as appropriate to code CS Extension based on a statement of T when no other information is available. **Note 4**: Use code 300 for localized tumor only if no information is available to assign code 100, 110, 120, 160. 170, 200, 390, or 400.
Code Description AJCC 7 T AJCC 6 T Summary Stage 1977 T Summary Stage 2000 T
000 In situ, intraepithelial, noninvasive
Dysplasia
Tumor size less than 0.5 millimeters (mm)
Tis Tis IS IS
050 OBSOLETE DATA RETAINED AND REVIEWED V0203
See code 000

(Adeno)carcinoma in a polyp, noninvasive
Tis Tis IS IS
100 Tumor confined to mucosa, NOS including intramucosal, NOS Tis T1 L L
110 Invades lamina propria, including lamina propria in a polyp Extension Size AJCC7 T1 L L
120 Invades muscularis mucosae, including muscularis mucosae in a polyp Extension Size AJCC7 T1 L L
130 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 110, 120, 160

Confined to head of polyp
Extension to stalk
Extension Size AJCC7 T1 L L
140 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 110, 120,160

Confined to stalk of polyp
Extension Size AJCC7 T1 L L
150 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 110, 120, 160

Tumor in polyp, NOS
Extension Size AJCC7 T1 L L
160 Invades submucosa (superficial invasion), including submucosa in a polyp Extension Size AJCC7 T1 L L
170 Stated as T1 with no other information on extension Extension Size AJCC7 T1 L L
200 Invades into but not through muscularis propria T2 T2a L L
300 Localized, NOS
Implants inside stomach
Extension Size AJCC7 T1 L L
340 OBSOLETE DATA CONVERTED V0203
See code 170

Stated as T1, NOS with no other information on extension
ERROR: ERROR: ERROR: ERROR:
350 OBSOLETE DATA RETAINED V0200

Linitis plastica (see Note 2) and no other information regarding extension is available.
ERROR: T2a RE L
390 Stated as T2 with no other information on extension T2 T2NOS L L
400 Invasion through muscularis propria or muscularis, NOS
Extension through wall, NOS
Perimuscular tissue invaded
Subserosa /(sub)serosal fat penetrated
T3 T2b L L
450 Extension to adjacent (connective) tissue
WITHOUT perforation of visceral peritoneum:
Gastric artery
Ligaments:
Gastrocolic
Gastrohepatic
Gastrosplenic
Omentum, NOS:
Greater
Lesser
Perigastric fat
T3 T2b RE RE
480 Stated as T3 with no other information on extension T3 T3 RE RE
490 OBSOLETE DATA CONVERTED V0203
See code 810

Stated as T4, [NOS] with no other information on extension
ERROR: ERROR: ERROR: ERROR:
500 Invasion of/through serosa (mesothelium)
(tunica serosa) (visceral peritoneum)
Including perforation of visceral peritoneum covering the gastric ligaments or the omentum
WITHOUT invasion of adjacent structures
T4 T3 RE RE
550 500 + 450

Invasion of tissues in code 500 plus extension to structures in code 450
T4 T3 RE RE
600 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 610, 650

Diaphragm
Duodenum via serosa or NOS
Esophagus via serosa
Ileum
Jejunum
Liver
Pancreas
Small intestine, NOS
Spleen
Transverse colon/mesocolon (including flexures)
Celiac axis
Aorta
T4 T4 RE RE
610 Diaphragm
Duodenum via serosa or NOS
Esophagus via serosa
Ileum
Jejunum
Liver
Pancreas
Small intestine, NOS
Spleen
Transverse colon/mesocolon (including flexures)
T4 T4 RE RE
650 Aorta
Celiac axis
T4 T4 D D
700 Abdominal wall
Adrenal gland
Kidney
Retroperitoneum
T4 T4 D D
800 Further contiguous extension T4 T4 D D
810 Stated as T4 with no other information on extension T4 T4 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 CS Extension codes 110-170 and 300 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.