C4A.61 ICD-10-CM Code: Merkel cell carcinoma of right upper limb, including shoulder
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Inpatient Payment Groups (MS-DRG)
MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0 (FY2026), Appendix B.
- MS-DRG 595 — MAJOR SKIN DISORDERS WITH MCC (MDC 09)
- MS-DRG 596 — MAJOR SKIN DISORDERS WITHOUT MCC (MDC 09)
A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.
Risk Adjustment (CMS-HCC)
Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.
- HCC 21 — Lymphoma and Other Cancers (supersedes HCC 22, HCC 23)
Other models: CMS-HCC V22 HCC 12 · RxHCC V08 HCC 22
Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.
Code Set: Valid FY2026 and FY2027. FY2026 took effect October 1, 2025.
Official Registry Overview & Definition
Nearest Codes in This Family
Official ICD-10-CM classifications closest to C4A.61 in its code family, with their registry titles.
- 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.6 — Merkel cell carcinoma of upper limb, including shoulder
- C4A.60 — Merkel cell carcinoma of unspecified upper limb, including shoulder
- C4A.62 — Merkel cell carcinoma of left upper limb, including shoulder
- C4A.7 — Merkel cell carcinoma of lower limb, including hip
- 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