CS Extension

Notes

**Note 1**: AJCC does not include a Tis category for gastrointestinal stromal tumors (GIST). Any case with a CS Extension code of 000 is mapped to TX for AJCC 7 stage and in situ Summary Stage. **Note 2**: Intraluminal or intramural extension to esophagus and duodenum is classified by the depth of greatest invasion in any of these sites, including stomach. **Note 3**: The assignment of T categories for GISTs 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 340, 390, 395, and 398 as appropriate to code CS Extension based on a statement of T when no other extension information is available. **Note 4**: Use code 150 only if GIST is described as arising in a polyp. Do not use this code for GIST described as arising in the wall of the appendix and extending into the lumen with a polypoid appearance. **Note 5**: Use code 300 for localized cases only if no information is available to assign a more specific code.
Code Description AJCC 7 T AJCC 6 T Summary Stage 1977 T Summary Stage 2000 T
000 In situ, intraepithelial, noninvasive TX NA IS IS
050 OBSOLETE DATA RETAINED AND REVIEWED V0203
See code 000

(Adeno)carcinoma, noninvasive, in a polyp
TX NA IS IS
100 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 155 and 165

Invasive tumor confined to mucosa, NOS (including intramucosal, NOS)
Extension Size AJCC7 NA L L
110 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 155 and 165

Invades lamina propria
Extension Size AJCC7 NA L L
120 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 155 and 165

Invades muscularis mucosae
Extension Size AJCC7 NA L L
130 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 155 and 165

Confined to head of polyp
Extension to stalk of polyp
Extension Size AJCC7 NA L L
140 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 155 and 165

Confined to stalk of polyp
Extension Size AJCC7 NA L L
150 Invasive tumor in polyp, NOS Extension Size AJCC7 NA L L
155 Tumor confined to muscular wall Extension Size AJCC7 NA L L
160 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 155 and 165

Invades submucosa (superficial invasion)
Extension Size AJCC7 NA L L
165 Tumor invades through submucosa and muscularis mucosae to involve mucosa Extension Size AJCC7 NA L L
200 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 155 and 165

Invades into but not through muscularis propria
Extension Size AJCC7 NA L L
300 Implants inside stomach
Localized, NOS
Extension Size AJCC7 NA L L
340 Stated as T1 with no other information on extension Extension Size AJCC7 NA L L
350 OBSOLETE DATA RETAINED V0200

Linitis plastica and no other information regarding extension is available
ERROR: NA RE L
390 Stated as T2 with no other information on extension Extension Size AJCC7 NA L L
395 Stated as T3 with no other information on extension Extension Size AJCC7 NA L L
398 Stated as T4 with no other information on extension Extension Size AJCC7 NA L L
400 Invasion through muscularis propria or muscularis, NOS
Extension through wall, NOS
Perimuscular tissue invaded
Subserosal tissue/(sub)serosal fat invaded

Note: In V0203 ONLY, code 400 had a different meaning, but the original description of the code has been restored in V0204.
Extension Size AJCC7 NA L L
440 Intraluminal extension to esophagus or duodenum Extension Size AJCC7 NA RE L
450 Extension to adjacent (connective) tissue
WITHOUT perforation of visceral peritoneum:
Gastric artery
Ligaments:
Gastrocolic
Gastrohepatic
Gastrosplenic
Omentum, NOS:
Greater
Lesser
Perigastric fat
Extension Size AJCC7 NA RE RE
458 Fat, NOS Extension Size AJCC7 NA RE RE
480 OBSOLETE DATA CONVERTED V0203
See code 395

Stated as T3 with no other information on extension
ERROR: ERROR: ERROR: ERROR:
490 OBSOLETE DATA CONVERTED V0203
See code 398

Stated as T4 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
Extension Size AJCC7 NA RE RE
550 500 + 450 Extension Size AJCC7 NA RE RE
560 Invasion of/through serosa with invasion of/through mucosa Extension Size AJCC7 NA RE RE
600 OBSOLETE DATA RETAINED AND REVIEWED V0203
See codes 610 and 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
Extension Size AJCC7 NA RE RE
610 Diaphragm
Duodenum via serosa Duodenum, NOS
Esophagus via serosa
Ileum
Jejunum
Liver
Pancreas
Small intestine, NOS
Spleen
Transverse colon/mesocolon (including flexures)
Extension Size AJCC7 NA RE RE
650 Aorta
Celiac axis
Extension Size AJCC7 NA D D
700 Abdominal wall
Adrenal gland
Kidney
Retroperitoneum
Extension Size AJCC7 NA D D
800 Further contiguous extension Extension Size AJCC7 NA D D
950 No evidence of primary tumor T0 NA U U
999 Unknown; extension not stated
Primary tumor cannot be assessed
Not documented in patient record
TX NA U U
- For CS Extension codes -100-800 ONLY, the T category is assigned based on the value of CS Tumor Size, as shown in the Extension Size AJCC 7 Table for this schema.