ICD10
ICD-10 Code C4A.6: Merkel cell carcinoma of upper limb, including shoulder
Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026
What is this code?
ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Neoplasms (C00-D49).
When is it used?
- May be used when a clinician documents merkel cell carcinoma of upper limb, including shoulder in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
- This entry may represent a broader category rather than the most specific billable code.
Code hierarchy
chapter
2Neoplasms (C00-D49)
block
C00-C96Malignant neoplasms
block
C00-C75Malignant neoplasms, stated or presumed to be primary (of specified sites), and certain specified histologies, except neuroendocrine, and of lymphoid, hematopoietic and related tissue
block
C43-C44Melanoma and other malignant neoplasms of skin
category
C4AMerkel cell carcinoma
currentC4A
Where you may see this code
You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.
Related specialists
OncologistGeneral Physician
Related codes
Sibling codes
C4A.0Merkel cell carcinoma of lipbillableC4A.1Merkel cell carcinoma of eyelid, including canthusC4A.2Merkel cell carcinoma of ear and external auricular canalC4A.3Merkel cell carcinoma of other and unspecified parts of faceC4A.4Merkel cell carcinoma of scalp and neckbillableC4A.5Merkel cell carcinoma of trunkC4A.7Merkel cell carcinoma of lower limb, including hipC4A.8Merkel cell carcinoma of overlapping sitesbillableC4A.9Merkel cell carcinoma, unspecifiedbillable
Coding guidelines
Common synonyms
Merkel cell carcinoma of upper limb, including shoulder
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.