An official website of the United States government
ICD-O-3 Site Codes
Related Adjectives
- Colon—colo, colono-
- Rectum—rectal, recto-
- Anus—procto-, ano-
- Colon and rectum—large bowel, large intestine, colorectal
| ICD-O-2/3 | Term |
|---|---|
| C18.0 | Cecum |
| C18.1 | Appendix |
| C18.2 | Ascending colon; Right colon |
| C18.3 | Hepatic flexure of colon |
| C18.4 | Transverse colon |
| C18.5 | Splenic flexure of colon |
| C18.6 | Descending colon; Left colon |
| C18.7 | Sigmoid colon |
| C18.8 | Overlapping lesion of colon |
| C18.9 | Colon, NOS |
| ICD-O-2/3 | Term |
|---|---|
| C19.9 | Rectosigmoid junction |
| ICD-O-2/3 | Term |
|---|---|
| C20.9 | Rectum, NOS |
| ICD-O-2/3 | Term |
|---|---|
| C21.0 | Anus, NOS (excludes Skin of anus and Perianal skin C44.5) |
| C21.1 | Anal canal |
| C21.2 | Cloacogenic zone |
| C21.8 | Overlapping lesion of rectum, anus and anal canal |
Each ICD-O four-digit sub site within the colon and rectum is considered a separate primary site.