C4A
Non-billableMerkel cell carcinoma
Merkel cell carcinoma
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Cross-references
UMLS
Child Codes (10)
C4A.0Merkel cell carcinoma of lip
C4A.1Merkel cell carcinoma of eyelid, including canthus
C4A.2Merkel cell carcinoma of ear and external auricular canal
C4A.3Merkel cell carcinoma of other and unspecified parts of face
C4A.4Merkel cell carcinoma of scalp and neck
C4A.5Merkel cell carcinoma of trunk
C4A.6Merkel cell carcinoma of upper limb, including shoulder
C4A.7Merkel cell carcinoma of lower limb, including hip
C4A.8Merkel cell carcinoma of overlapping sites
C4A.9Merkel cell carcinoma, unspecified
Also Known As / Clinical Terms(36)
UMLS
- Anaplastic carcinoma of the skinC0007129
- Apudoma of skinC0007129
- Apudoma of skin (disorder)C0007129
- Cancer, Merkel CellC0007129
- Carcinoma, Merkel CellC0007129
- Cell Cancer, MerkelC0007129
- Cutaneous APUDomaC0007129
- MCCC0007129
- Merkel Cell CancerC0007129
- Merkel Cell CarcinomaC0007129
- Merkel Cell TumorC0007129
- Merkel cell cancer of the skinC0007129
- Merkel cell carcinomaC0007129
- Merkel cell carcinoma (disorder)C0007129
- Merkel cell carcinoma (morphologic abnormality)C0007129
- Merkel cell carcinoma NOSC0007129
- Merkel cell skin cancerC0007129
- Merkel cell tumorC0007129
- Merkel cell tumourC0007129
- Merkle TumorsC0007129
- Neuroendocrine carcinoma of the skinC0007129
- Neuroendocrine tumor of the skinC0007129
- Neuroendocrine tumour of the skinC0007129
- Primary cutaneous neuroendocrine carcinomaC0007129
- Primary small cell carcinoma of the skinC0007129
- Primary undifferentiated carcinoma of the skinC0007129
- Tumor, Merkel CellC0007129
- Tumors, MerkleC0007129
- carcinoma cell merkelsC0007129
- carcinoma neuroendocrine skinC0007129
- cell merkel tumorsC0007129
- mccC0007129
- merkel cell cancerC0007129
- merkel cell carcinomaC0007129
- merkel cell tumorC0007129
- merkel cell tumourC0007129
Common questions
What is the ICD-10-CM code for Merkel cell carcinoma?
Merkel cell carcinoma is coded as C4A in ICD-10-CM.
What is ICD-10 code C4A?
C4A is the ICD-10-CM identifier for Merkel cell carcinoma. It is included in the official 2025 release of ICD-10-CM published by CMS and NCHS.
Why is C4A non-billable?
C4A is a category code; ICD-10-CM requires the most specific child code for claim submission. The billable child codes under C4A are: C4A.0, C4A.10, C4A.111, C4A.112, C4A.121, C4A.122, and 18 more.
What chapter does C4A belong to?
C4A is in Chapter 2: Neoplasms.
What are the synonyms for Merkel cell carcinoma?
In clinical text, merkel cell carcinoma is also written as: Anaplastic carcinoma of the skin, Apudoma of skin, Apudoma of skin (disorder), Cancer, Merkel Cell, Carcinoma, Merkel Cell, Cell Cancer, Merkel, and 27 more. Sourced from UMLS Metathesaurus.
What is the UMLS mapping for C4A?
C4A maps to UMLS C0007129.
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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.