C21
Non-billableMalignant neoplasm of anus and anal canal
Malignant neoplasm of anus and anal canal
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
- Kaposi's sarcoma of gastrointestinal sites (C46.4)
Excludes 2
Conditions not included here, but the patient may have both
- gastrointestinal stromal tumors (C49.A-)
- malignant carcinoid tumors of the colon (C7A.02-)
- malignant melanoma of anal margin (C43.51)
- malignant melanoma of anal skin (C43.51)
- malignant melanoma of perianal skin (C43.51)
- other and unspecified malignant neoplasm of anal margin (C44.500, C44.510, C44.520, C44.590)
- other and unspecified malignant neoplasm of anal skin (C44.500, C44.510, C44.520, C44.590)
- other and unspecified malignant neoplasm of perianal skin (C44.500, C44.510, C44.520, C44.590)
Child Codes (4)
Also Known As / Clinical Terms
Frequently Asked Questions
What is ICD-10 code C21?
ICD-10-CM code C21 represents "Malignant neoplasm of anus and anal canal". It is a non-billable header code — use a more specific child code for billing purposes.
Is C21 a billable code?
No, C21 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 4 child codes under C21.
What chapter is C21 in?
C21 is in Chapter 2: Neoplasms (codes C00-D49).
What codes cannot be used with C21?
C21 has Excludes1 notes indicating codes that cannot be used together with it, including: Kaposi's sarcoma of gastrointestinal sites (C46.4).
What are the subcategories under C21?
C21 has 4 child codes, including: C21.0 (Malignant neoplasm of anus, unspecified), C21.1 (Malignant neoplasm of anal canal), C21.2 (Malignant neoplasm of cloacogenic zone), C21.8 (Malig neoplasm of ovrlp sites of rectum, anus and anal canal).
What are the UMLS CUIs for C21?
C21 is linked to 1 UMLS Concept Unique Identifier: C0346631. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.