CS Extension (Colon)

Note 1: Ignore intraluminal extension to adjacent segment(s) of colon/rectum or to the ileum from the cecum; codedepth of invasion or extracolonic spread as indicated.

Note 2: A tumor nodule in the pericolic adipose tissue of a primary carcinoma without histologic evidence of residual lymph node in the nodule is classified as a regional lymph node metastasis if the nodule has the form and smooth contour of a lymph node, or if the contour is not described. If the nodule has an irregular contour, it should be coded in CS Extension as code 45.

Note 3: Codes 60-80 are used for contiguous extension from the site of origin. Discontinuous involvement is coded in CS Mets at DX.

Code	Description	TNM	SS77	SS2000
00	In situ; noninvasive; intraepithelial	Tis	IS	IS
05	(Adeno)carcinoma in a polyp or adenoma, noninvasive	Tis	IS	IS
10	Invasive tumor confined to mucosa, NOS (including intramucosal, NOS)	T1	L	L
11	Lamina propria, including lamina propria in the stalk of a polyp	T1	L	L
12	Muscularis mucosae, including muscularis mucosae in the stalk of a polyp	T1	L	L
13	Confined to head of polyp, NOS	T1	L	L
14	Confined to stalk of polyp, NOS	T1	L	L
15	Invasive tumor in polyp, NOS	T1	L	L
16	Invades submucosa (superficial invasion), including submucosa in the stalk of a polyp	T1	L	L
20	Muscularis propria invaded	T2	L	L
30	Localized, NOS Confined to colon, NOS	T1	L	L
40	Extension through wall, NOS Invasion through muscularis propria or muscularis, NOS Non-peritonealized pericolic tissues invaded Perimuscular tissue invaded Subserosal tissue/(sub)serosal fat invaded Transmural, NOS	T3	L	L
42	Fat, NOS	T3	RE	RE
45	Extension to: All colon sites: Adjacent tissue(s), NOS Connective tissue Mesenteric fat Mesentery Mesocolon Pericolic fat Ascending and descending colon Retroperitoneal fat Transverse colon/flexures Gastrocolic ligament Greater omentum	T3	RE	RE
46	Adherent to other organs or structures, but no microscopic tumor found in adhesion(s)	T3	RE	RE
50	Invasion of/through serosa (mesothelium) (visceral peritoneum)	T4	RE	RE
55	Any of [(42) to (45)] + (50)	T4	RE	RE
57	Adherent to other organs or structures, NOS	T4	RE	RE
60	All colon sites: Small intestine Cecum and appendix: Greater omentum Ascending colon: Greater omentum Liver, right lobe Tranverse colon and flexures: Gallbladder/bile ducts Kidney Liver Pancreas Spleen Stomach Descending colon: Greater omentum Pelvic wall Spleen Sigmoid colon: Greater omentum Pelvic wall	T4	RE	RE
65	All colon sites: Abdominal wall Retroperitoneum (excluding fat)	T4	RE	RE
66	Ascending colon: Right kidney Right ureter Descending colon: Left kidney Left ureter	T4	RE	RE
70	Cecum, appendix, ascending, descending and sigmoid colon: Fallopian tube Ovary Uterus	T4	D	D
75	All colon sites unless otherwise stated above: Adrenal (suprarenal) gland Bladder Diaphragm Fistula to skin Gallbladder Other segment(s) of colon via serosa	T4	D	D
80	Further contiguous extension: Cecum and appendix: Kidney Liver Ureter Transverse colon and flexures: Ureter Sigmoid colon: Cul de sac (rectouterine pouch) Ureter Other contiguous extension	T4	D	D
95	No evidence of primary tumor	T0	U	U
99	Unknown extension Primary tumor cannot be assessed Not documented in patient record	TX	U	U