CS Lymph Nodes: Colon

Note 1: Code only regional nodes and nodes, NOS, in this field. Distant nodes are coded in the field Mets at DX.

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: Inferior mesenteric nodes are coded in CS Mets at DX for cecum, appendix, ascending colon, transverse colon, and hepatic flexure. Superior mesenteric nodes are coded in CS Mets at DX for all colon sites.

Code Description TNM SS77 SS2000
00 None; no regional lymph node involvement N0 NONE NONE
10 Regional lymph node(s) for all colon sites:
  • Colic (NOS)
  • Epicolic (adjacent to bowel wall)
  • Mesocolic (NOS)
  • Paracolic/pericolic
  • Nodule(s) or foci in pericolic fat/adjacent mesentery/
  • mesocolic fat
20 Regional lymph node(s), for specific subsites:
  • Cecum and appendix:
  • Cecal: anterior (prececal), posterior (retrocecal); NOS
  • Ileocolic
  • Right colic
  • Ascending colon:
  • Ileocolic
  • Middle colic
  • Right colic
  • Transverse colon and flexures:
  • Inferior mesenteric for splenic flexure only
  • Left colic for splenic flexure only
  • Middle colic
  • Right colic for hepatic flexure only
  • Descending colon:
  • Inferior mesenteric
  • Left colic
  • Sigmoid
  • Sigmoid colon:
  • Inferior mesenteric
  • Sigmoidal (sigmoid mesenteric)
  • Superior hemorrhoidal
  • Superior rectal
30 Regional lymph node(s) for all colon sites:
  • Mesenteric, NOS
  • Regional lymph node(s), NOS
80 Lymph nodes, NOS * RN RN
  • Unknown; not stated
  • Regional lymph node(s) cannot be assessed
  • Not documented in patient record

* For codes 10-80 ONLY, the N category is assigned based on the value of Reg LN Pos, using the Lymph Nodes
Number Positive Table for this site.

Close Window