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)
Excludes 2
Conditions not included here, but the patient may have both
- •gastrointestinal stromal tumorsA-)C49
- malignant carcinoid tumors of the colon (C7A.02-)
- •malignant melanoma of anal marginC43.51
- •malignant melanoma of anal skinC43.51
- •malignant melanoma of perianal skinC43.51
- •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)
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(1)
Frequently Asked Questions
What is the ICD-10 code for malignant neoplasm of anus and anal canal?
The ICD-10-CM code for malignant neoplasm of anus and anal canal is C21. The full clinical description is "Malignant neoplasm of anus and anal canal". C21 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code C21 mean?
ICD-10-CM code C21 represents “Malignant neoplasm of anus and anal canal”. It is classified under Chapter 2: Neoplasms and 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.
How does C21 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like malignant neoplasm of anus and anal canal affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of C21?
C21 maps to the ICD-11 code: 2C00.Z (Malignant neoplasms of anus or anal canal, unspecified).
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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.