C4A.8 Merkel cell carcinoma of overlapping sites
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The ICD-10-CM code for Merkel cell carcinoma of overlapping sites is C4A.8 (FY2026). It is a billable, claim-ready diagnosis code.
Classification
- Chapter
- 2: Neoplasms (C00-D49)
- Section
- C43-C44: Melanoma and other malignant neoplasms of skin (C43-C44)
- Category C4A
- 33 codes (24 billable)
- FY2026 Status
- Stable since FY2024
Also Known As
ICD-10-CM Alphabetic Index entries that lead to C4A.8:
- Carcinoma (malignant) › Merkel cell › overlapping sites
U.S. Hospital Utilization
C4A.8 appeared in too few sampled U.S. inpatient stays in 2023 to report a national estimate (AHRQ suppresses counts of 10 or fewer) — a rare inpatient diagnosis.
Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.
References
Cite This Page
Reference C4A.8 with the canonical source and edition:
C4A.8 — Merkel cell carcinoma of overlapping sites. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/C4A.8
Canonical URL: https://icd10codingpro.com/codes/C4A.8