C4A Merkel cell carcinoma

⚠ Non-Billable ICD-10-CM 2026
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The ICD-10-CM code for Merkel cell carcinoma is C4A (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Section
C43-C44: Melanoma and other malignant neoplasms of skin (C43-C44)
Category C4A
33 codes (24 billable)
FY2026 Status
Stable since FY2024

References

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Reference C4A with the canonical source and edition:

C4A — Merkel cell carcinoma. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/C4A

Canonical URL: https://icd10codingpro.com/codes/C4A

Related Codes

More Specific Codes

C4A.0 Merkel cell carcinoma of lip C4A.1 Merkel cell carcinoma of eyelid, including canthus C4A.2 Merkel cell carcinoma of ear and external auricular canal C4A.3 Merkel cell carcinoma of other and unspecified parts of face C4A.4 Merkel cell carcinoma of scalp and neck C4A.5 Merkel cell carcinoma of trunk C4A.6 Merkel cell carcinoma of upper limb, including shoulder C4A.7 Merkel cell carcinoma of lower limb, including hip C4A.8 Merkel cell carcinoma of overlapping sites C4A.9 Merkel cell carcinoma, unspecified

All Codes in C4A

Every most-specific code under C4A Merkel cell carcinoma (24 codes):

Show the complete C4A code list
C4A.0 Merkel cell carcinoma of lip C4A.10 Merkel cell carcinoma of unspecified eyelid, including canthus C4A.111 Merkel cell carcinoma of right upper eyelid, including canthus C4A.112 Merkel cell carcinoma of right lower eyelid, including canthus C4A.121 Merkel cell carcinoma of left upper eyelid, including canthus C4A.122 Merkel cell carcinoma of left lower eyelid, including canthus C4A.20 Merkel cell carcinoma of unspecified ear and external auricular canal C4A.21 Merkel cell carcinoma of right ear and external auricular canal C4A.22 Merkel cell carcinoma of left ear and external auricular canal C4A.30 Merkel cell carcinoma of unspecified part of face C4A.31 Merkel cell carcinoma of nose C4A.39 Merkel cell carcinoma of other parts of face C4A.4 Merkel cell carcinoma of scalp and neck C4A.51 Merkel cell carcinoma of anal skin C4A.52 Merkel cell carcinoma of skin of breast C4A.59 Merkel cell carcinoma of other part of trunk C4A.60 Merkel cell carcinoma of unspecified upper limb, including shoulder C4A.61 Merkel cell carcinoma of right upper limb, including shoulder C4A.62 Merkel cell carcinoma of left upper limb, including shoulder C4A.70 Merkel cell carcinoma of unspecified lower limb, including hip C4A.71 Merkel cell carcinoma of right lower limb, including hip C4A.72 Merkel cell carcinoma of left lower limb, including hip C4A.8 Merkel cell carcinoma of overlapping sites C4A.9 Merkel cell carcinoma, unspecified
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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